tuko Posted August 25, 2023 Share Posted August 25, 2023 On the xmod Defender 110 that I have, it has disc/drum brake setup which I'm personally not happy with the braking considering that the Defender is fully loaded with camping gear, rooftop tent, etc weighing in or around 3000kg all the time. I realize that someone may write that If it's all adjusted/serviced correctly, it's up to the task, but thats not what I'm looking for here, I'm asking how can I/we can use our imagination with some parts to make an improvement. The best example is Nick using a Disco 1 booster on his 109, which I followed his suggestions and use on the series hybrid. Two thumbs up on that Nick! At the time of restoring the Defender I did install a Disco 1 booster but it was MOT time for the Series hybrid too and it developed a leak on one of the diaphragms so I stole from Peter to pass the MOT. I reinstalled the large pancake booster and just left it at that till now. I have assembled a pile of parts for converting the rear of the Defender to disc brakes including a later ABS salisbury axle with disc's, cross drilled rear disc's LR018026CDG, another Disco 1 booster ANR2046 and Im pricing now a set of braided hose kit DA2402S. I've stripped the replacement axle and began reconditioning it including the calipers. Within the next 2 months the plan is to do the conversion with the parts that I have. I'm not too sure how to approach this project, should I do it in steps or approaching full guns blazing? LOL I'm guessing that a later Defender booster would work or will it because of it being ABS? I do know from already doing it, the Disco 1 booster does fit with modifications to the fork. I can assume that simply changing to disc's that it's going to make an improvement, but how far can I go till it's just a waste of time and or money? I'm thinking that the combination of all the parts of disc's, rotors, braided brake lines and a dual diaphragm booster it's going to make the difference that I want and need when touring with the Defender. What do you guys think, will it work? I look forward to constuctive comments and suggstions. Todd. Quote Link to comment Share on other sites More sharing options...
fmmv Posted August 25, 2023 Share Posted August 25, 2023 Not sure from your pics what will supply the vacuum but if it is weak then the brakes will lack 'bite'. I'd have a measure of the vacuum. I think if you put reasonable pads in ( I am using LOF performance pads and they seem to be quite good, but there are lots of others) the brakes will work fine, given sufficient shove for 'normal' (ie sensible) use. But if the vacuum is weak or there is a leak (eg where the non return valve attaches to the servo, or the valve itself) the brakes will feel OK on light applications but will need elephantine pressure to stop quickly. I'm planning to install an electric vac pump (assuming I live long enough to do it), as the 300tdi pumps seem to be a bit of a lottery as to whether they work for very long. Quote Link to comment Share on other sites More sharing options...
hurbie Posted August 25, 2023 Share Posted August 25, 2023 and remember , your rear brake's do only at most 40% of the braking (probebly much less) , so your gain wil not be much over correct adjusted drums .... Quote Link to comment Share on other sites More sharing options...
Wytze Posted August 25, 2023 Share Posted August 25, 2023 4 hours ago, tuko said: On the xmod Defender 110 that I have, it has disc/drum brake setup which I'm personally not happy with the braking considering that the Defender is fully loaded with camping gear, rooftop tent, etc weighing in or around 3000kg all the time. I realize that someone may write that If it's all adjusted/serviced correctly, it's up to the task, but thats not what I'm looking for here, I'm asking how can I/we can use our imagination with some parts to make an improvement. The best example is Nick using a Disco 1 booster on his 109, which I followed his suggestions and use on the series hybrid. Two thumbs up on that Nick! At the time of restoring the Defender I did install a Disco 1 booster but it was MOT time for the Series hybrid too and it developed a leak on one of the diaphragms so I stole from Peter to pass the MOT. I reinstalled the large pancake booster and just left it at that till now. I have assembled a pile of parts for converting the rear of the Defender to disc brakes including a later ABS salisbury axle with disc's, cross drilled rear disc's LR018026CDG, another Disco 1 booster ANR2046 and Im pricing now a set of braided hose kit DA2402S. I've stripped the replacement axle and began reconditioning it including the calipers. Within the next 2 months the plan is to do the conversion with the parts that I have. I'm not too sure how to approach this project, should I do it in steps or approaching full guns blazing? LOL I'm guessing that a later Defender booster would work or will it because of it being ABS? I do know from already doing it, the Disco 1 booster does fit with modifications to the fork. I can assume that simply changing to disc's that it's going to make an improvement, but how far can I go till it's just a waste of time and or money? I'm thinking that the combination of all the parts of disc's, rotors, braided brake lines and a dual diaphragm booster it's going to make the difference that I want and need when touring with the Defender. What do you guys think, will it work? I look forward to constuctive comments and suggstions. Todd. On mine there are allso disc's all round. Vented front's , braided hoses, and the single large booster, mintex pad's all round and a vacuupump on the altenator. She can lock all wheel's on 35's. She's about 2600kg all packed up. And i trust my brakes. 1 Quote Link to comment Share on other sites More sharing options...
tuko Posted August 25, 2023 Author Share Posted August 25, 2023 8 hours ago, fmmv said: Not sure from your pics what will supply the vacuum but if it is weak then the brakes will lack 'bite'. I'd have a measure of the vacuum. I think if you put reasonable pads in ( I am using LOF performance pads and they seem to be quite good, but there are lots of others) the brakes will work fine, given sufficient shove for 'normal' (ie sensible) use. But if the vacuum is weak or there is a leak (eg where the non return valve attaches to the servo, or the valve itself) the brakes will feel OK on light applications but will need elephantine pressure to stop quickly. I'm planning to install an electric vac pump (assuming I live long enough to do it), as the 300tdi pumps seem to be a bit of a lottery as to whether they work for very long. Ja the pictures don't tell you that I installed a 300tdi, I never thought of an electric vac pump and that is a good suggestion. I have to look into that if the parts that I have here now don't give me what I'm hoping or expecting from them. Quote Link to comment Share on other sites More sharing options...
tuko Posted August 25, 2023 Author Share Posted August 25, 2023 3 hours ago, Wytze said: On mine there are allso disc's all round. Vented front's , braided hoses, and the single large booster, mintex pad's all round and a vacuupump on the altenator. She can lock all wheel's on 35's. She's about 2600kg all packed up. And i trust my brakes. Eventually I will have disc's allround, braided hoses and new pads like you but I have to ask, am I correct in thinking that you have a td5? I ask because of the vac pump on the alt, isn't that a TD5 thing? Quote Link to comment Share on other sites More sharing options...
reb78 Posted August 25, 2023 Share Posted August 25, 2023 I know its not what you want to hear but why the obsession with discs on the rear? Its the absolute bottom of my list of mods. I can lock my 110 up on a dry road. I tow up to the legal limit and the brakes are spot on, all maintained properly and totally stock. Theres a few points... 1. Properly adjusted drums? 2. Have you rebuilt or replaced the front calipers? Reason for asking is that people never keep up with the reccomended brake fluid changes. When I rebuilt my calipers I found the lower fluid channels were gummed and blocked with rubber seal goop. No fluid was passing. I wonder how many older calipers are like this and reliant on the upper fluid gallery for flow between the two halves of the caliper... the WSM states not to split them so I guess many dont and dont spot this and clear the gallery. Even vented discs are not that necessary if you arent towing down the alps all day.. Quote Link to comment Share on other sites More sharing options...
Wytze Posted August 26, 2023 Share Posted August 26, 2023 7 hours ago, tuko said: Eventually I will have disc's allround, braided hoses and new pads like you but I have to ask, am I correct in thinking that you have a td5? I ask because of the vac pump on the alt, isn't that a TD5 thing? No, i have a heavy Mazda 35slt. With a 75 amp altenator. A 12 volt vacuum pump could work aswell, i think Quote Link to comment Share on other sites More sharing options...
Sigi_H Posted August 26, 2023 Share Posted August 26, 2023 Just to mention it: Drum brakes are not worse because they have considerably more active braking surface in the drums. The main disadvantage is maintenance. The LR drum brakes do not even have automatic adjusters. Another disadvantage is their susceptibility to fading. They are not as stable as vented brake discs, especially in the mountains. All this is enough to replace them with discs, but they are no less effective in normal everyday use. 2 Quote Link to comment Share on other sites More sharing options...
tuko Posted August 26, 2023 Author Share Posted August 26, 2023 26 minutes ago, Sigi_H said: Just to mention it: Drum brakes are not worse because they have considerably more active braking surface in the drums. The main disadvantage is maintenance. The LR drum brakes do not even have automatic adjusters. Another disadvantage is their susceptibility to fading. They are not as stable as vented brake discs, especially in the mountains. All this is enough to replace them with discs, but they are no less effective in normal everyday use. Hej Sigi, No arguments with your comments and reasoning, also that the ease of visual inspections of the brakes is another disadvantage. I can add from my own experience with the series hybrid, changing to disc's all around, braided hoses, groove/drilled disc's coupled with the Disco 1 booster made a considerable difference with braking. The difference was especially noted when the series hybrid was fully loaded with the rooftop tent, awning, fridge and all of the camping gear. Never is there any fears with the brakes wheather I'm in the mountains or down in the fjords, the calipers clamping power is amazing and always there. Because of maybe being spoiled with the braking setup that I have in the series hybrid and experiencing the so so brakes in the Defender, I want to upgrade. Quote Link to comment Share on other sites More sharing options...
muzaz Posted August 26, 2023 Share Posted August 26, 2023 One reason I would change over to disc is for offroad in mud etc. It's difficult to clean without taking everything apart, and will affect braking till they dry up. 1 Quote Link to comment Share on other sites More sharing options...
tuko Posted August 26, 2023 Author Share Posted August 26, 2023 (edited) 10 hours ago, reb78 said: I know its not what you want to hear but why the obsession with discs on the rear? Its the absolute bottom of my list of mods. I can lock my 110 up on a dry road. I tow up to the legal limit and the brakes are spot on, all maintained properly and totally stock. Theres a few points... 1. Properly adjusted drums? 2. Have you rebuilt or replaced the front calipers? Reason for asking is that people never keep up with the reccomended brake fluid changes. When I rebuilt my calipers I found the lower fluid channels were gummed and blocked with rubber seal goop. No fluid was passing. I wonder how many older calipers are like this and reliant on the upper fluid gallery for flow between the two halves of the caliper... the WSM states not to split them so I guess many dont and dont spot this and clear the gallery. Even vented discs are not that necessary if you arent towing down the alps all day.. My desire for disc's is solely based on my experience with them on the series hybrid, I know what I can have with some changes to the Defender. Yes, I had the WSM open in my phone next to me under the Defender, so they were adjusted to the best of my abilities anyways. I like your point about splitting the calipers and is something I do agree should be done. I had a stripped bolt one time on a front caliper and had to split the caliper, keeping it clean and not damaging the seal, I still to this day have no leaks or issues with that caliper. WIth that said, on the Defender a thorough flush of the brake fluid will be on the list to do. Edited August 26, 2023 by tuko Quote Link to comment Share on other sites More sharing options...
Snagger Posted August 26, 2023 Share Posted August 26, 2023 Brake upgrades are a regular bone of contention. Both sides of the argument can be simultaneously correct. I too found the standard 109 drum brake system to be sufficient to easily lock up on a solid tarmac road in dry conditions at low speed, and they were pretty reliable. Did they need upgrading to discs all round? No, but it was worth it as part of the axle swap. The complete Discovery brake system doesn’t stop the car any shorter in theory as it has (nearly) the same mass and the same tyres. However, apart from being far easier to clean and service and shedding heat faster, this being more resilient to brake fade (again, I had no problem fully laden in the Alps with the drums because I drove accordingly), they are FAR easier to modulate for hard braking without going over into lock-up. ABS would enhance that further, where on paper ABS should provide slightly longer braking distance but in reality provides significantly better braking by maintaining traction. Back to the question, are you fitting the ABS system? I appreciate your used rear axle is set up for it, but it doesn’t necessarily have to be connected and can be used “dumb”. That won’t cause compatibility issues with the rest of the system as long as the front brakes are also 110 spec and you have an appropriate “all-discs” master cylinder. As far as the servo goes, some may give more or less boost than others, but that is a preference matter rather than a safety or effectiveness issue unless you have significant difficulty in applying full braking force with your leg (eg. elderly or injured). So, I think you can safely use whatever fits. Just make sure to check the full throw on the pedal trunnion doesn’t exceed the travel available on the servo, or it could be possible to damage the servo with a hard pedal push while bleeding the system. Quote Link to comment Share on other sites More sharing options...
Ibex94 Posted August 26, 2023 Share Posted August 26, 2023 One thing to check out is the rear proportioning valve if fitted. My rear brakes failed me on the IVA brake testing which is quite a bit more stringent than the MOT requirements. My donor was a 1988 90 turbo, solid discs at the front drums at the rear. During my build I carried out a complete refurb of the brake system (apart from the proportioning valve which got a little ignored) and upgraded to vents at the front and solid discs at the rear. Calipers were stripped and rebuilt with news seals and stainless pistons, new OE discs were fitted. I then went for a replacement master cylinder and produced a complete set of bespoke set of cupronickel brake lines routed as carefully as possible to keep out the way of getting snagged, all are P clipped to the chassis and rear axle, I also fitted braided hoses. I took the truck for an MOT shake down before IVA and got a pass. At IVA I got both front to lock up but the rears were quite low, hence fail. Hand brake was also not good enough for IVA - I think I reused the shoes and I suspect there was some oil contamination. So while I got a replacement proportioning valve I decided to delete it as the truck has a ~100" wheelbase which should be slightly better than the 90 on brake balance and I wanted to be sure he went through at retest. I decided to get a replacement set of handbrake shoes and replaced them, everything appeared to be bone dry but I couldn't remember whether I replaced them during the build. At retest got a lock up from all 4 corners as well as the handbrake with the rear wheels in the rollers. Then got satisfactory results for the full range of brake force test the inspector runs through and got rated for 3500kg towing. Really please with the brake performance and pedal feel. Still to decide whether to put the proportioning valve back in. Quote Link to comment Share on other sites More sharing options...
tuko Posted August 26, 2023 Author Share Posted August 26, 2023 3 hours ago, Snagger said: Brake upgrades are a regular bone of contention. Both sides of the argument can be simultaneously correct. I too found the standard 109 drum brake system to be sufficient to easily lock up on a solid tarmac road in dry conditions at low speed, and they were pretty reliable. Did they need upgrading to discs all round? No, but it was worth it as part of the axle swap. The complete Discovery brake system doesn’t stop the car any shorter in theory as it has (nearly) the same mass and the same tyres. However, apart from being far easier to clean and service and shedding heat faster, this being more resilient to brake fade (again, I had no problem fully laden in the Alps with the drums because I drove accordingly), they are FAR easier to modulate for hard braking without going over into lock-up. ABS would enhance that further, where on paper ABS should provide slightly longer braking distance but in reality provides significantly better braking by maintaining traction. Back to the question, are you fitting the ABS system? I appreciate your used rear axle is set up for it, but it doesn’t necessarily have to be connected and can be used “dumb”. That won’t cause compatibility issues with the rest of the system as long as the front brakes are also 110 spec and you have an appropriate “all-discs” master cylinder. As far as the servo goes, some may give more or less boost than others, but that is a preference matter rather than a safety or effectiveness issue unless you have significant difficulty in applying full braking force with your leg (eg. elderly or injured). So, I think you can safely use whatever fits. Just make sure to check the full throw on the pedal trunnion doesn’t exceed the travel available on the servo, or it could be possible to damage the servo with a hard pedal push while bleeding the system. Hi Nick, Sorry I didn't make that clearer about the ABS, the axle is ABS but it will not be used on the Defender. The other thread that I have in the axle section, I was trying to figue out what my axle number is and Tony has told me how to finally figure that out. I was also wondering at the same time if there might be any issues if I made the axle backward compatable ( removing the ABS stuff ) but now believe that there is no probs. After reading your post I went out to the Defender to see what master cylinder I have installed, it's the 3 outlet port version ( 2 front & 1 rear ). Then I checked in the garage what I had over and found I have a Disco 1 non ABS 2 outlet port master cylinder. The Disco obviously had disc's all round so I'm assuming from your comments that I should change the master cylinder so that it matches the servo? I was thinking beforehand that it might be wiser to keep use the 3 outlet port master cylinder because if I did have one line rupture on the front, there would still be some braking on the other side. ?? Quote Link to comment Share on other sites More sharing options...
tuko Posted August 26, 2023 Author Share Posted August 26, 2023 1 hour ago, Ibex94 said: One thing to check out is the rear proportioning valve if fitted. My rear brakes failed me on the IVA brake testing which is quite a bit more stringent than the MOT requirements. My donor was a 1988 90 turbo, solid discs at the front drums at the rear. During my build I carried out a complete refurb of the brake system (apart from the proportioning valve which got a little ignored) and upgraded to vents at the front and solid discs at the rear. Calipers were stripped and rebuilt with news seals and stainless pistons, new OE discs were fitted. I then went for a replacement master cylinder and produced a complete set of bespoke set of cupronickel brake lines routed as carefully as possible to keep out the way of getting snagged, all are P clipped to the chassis and rear axle, I also fitted braided hoses. I took the truck for an MOT shake down before IVA and got a pass. At IVA I got both front to lock up but the rears were quite low, hence fail. Hand brake was also not good enough for IVA - I think I reused the shoes and I suspect there was some oil contamination. So while I got a replacement proportioning valve I decided to delete it as the truck has a ~100" wheelbase which should be slightly better than the 90 on brake balance and I wanted to be sure he went through at retest. I decided to get a replacement set of handbrake shoes and replaced them, everything appeared to be bone dry but I couldn't remember whether I replaced them during the build. At retest got a lock up from all 4 corners as well as the handbrake with the rear wheels in the rollers. Then got satisfactory results for the full range of brake force test the inspector runs through and got rated for 3500kg towing. Really please with the brake performance and pedal feel. Still to decide whether to put the proportioning valve back in. Another very infomative post, thank you. As for the proportioning valve, I honestly have no idea, but I do know that I have a g valve, other than that I have to get under the Defender to see whats there. I can think, it being a 1992 xmod, there must be a proportioning valve. AS for the hand brake, it holds the Defender in one spot. 😉 Quote Link to comment Share on other sites More sharing options...
Ibex94 Posted August 26, 2023 Share Posted August 26, 2023 6 hours ago, tuko said: Another very infomative post, thank you. As for the proportioning valve, I honestly have no idea, but I do know that I have a g valve, other than that I have to get under the Defender to see whats there. I can think, it being a 1992 xmod, there must be a proportioning valve. AS for the hand brake, it holds the Defender in one spot. 😉 You g valve serves the same purpose, higher the deceleration the more mass transfer to the front, the g valve reduces the rear brake force to compensate. 1 Quote Link to comment Share on other sites More sharing options...
Snagger Posted August 27, 2023 Share Posted August 27, 2023 11 hours ago, tuko said: Hi Nick, Sorry I didn't make that clearer about the ABS, the axle is ABS but it will not be used on the Defender. The other thread that I have in the axle section, I was trying to figue out what my axle number is and Tony has told me how to finally figure that out. I was also wondering at the same time if there might be any issues if I made the axle backward compatable ( removing the ABS stuff ) but now believe that there is no probs. After reading your post I went out to the Defender to see what master cylinder I have installed, it's the 3 outlet port version ( 2 front & 1 rear ). Then I checked in the garage what I had over and found I have a Disco 1 non ABS 2 outlet port master cylinder. The Disco obviously had disc's all round so I'm assuming from your comments that I should change the master cylinder so that it matches the servo? I was thinking beforehand that it might be wiser to keep use the 3 outlet port master cylinder because if I did have one line rupture on the front, there would still be some braking on the other side. ?? You can use either master, as I think they are internally identical and produce the same volume and pressure. Use whichever best fits the servo drum. I used a second hand (but mint condition) three port master that came with the servo and blanked off the right hand port with a plug that resembles a solid bleed nipple end (really just a bolt with a conical end). There is little benefit to having twin front lines apart from where engine bay routing requires it as if one line fails, both sides will lose pressure - it’s not the same as the split between front and rear brakes, which are hydraulically independent. I suspect the three line system had the benefit of higher volume flow to the front to help with ABS activations, but I have had no problem on the 109 just using one port for the front - you will get the same volume transfer for a given pedal movement; it might theoretically take a fraction longer because of the more restricted piping than having separate hoses, but I have not had any brake lag or dragging. 1 Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted August 28, 2023 Share Posted August 28, 2023 Todd, IIRC you can't use the Defender ABS servo because the master cylinder mounting is different. The matching master cylinder doesn't have enough ports for a non ABS system. I'm using LoF sports pads which are very good 👍 HTH Mo Quote Link to comment Share on other sites More sharing options...
tuko Posted August 28, 2023 Author Share Posted August 28, 2023 5 hours ago, Mo Murphy said: Todd, IIRC you can't use the Defender ABS servo because the master cylinder mounting is different. The matching master cylinder doesn't have enough ports for a non ABS system. I'm using LoF sports pads which are very good 👍 HTH Mo Mo, Sport pads, is there a brand that I should stay away from? I seem to remember reading one time or another that some hard sport pads sqeal when used? More effective pads, yes I will be looking at that. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted August 28, 2023 Share Posted August 28, 2023 LoF is the brand. 1 Quote Link to comment Share on other sites More sharing options...
rusty_wingnut Posted August 29, 2023 Share Posted August 29, 2023 I've got LOF fast road or something spec pads and they're good. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted August 29, 2023 Share Posted August 29, 2023 Worth noting that vented/grooved/drilled discs don't stop you any better than solid discs - they just let you do more hard braking before they overheat. Unless you're boiling your brake fluid on a regular basis there's no benefit at all in buying flashy discs, especially on the rears. Given how hard it is to boil the brakes even on a heavily laden vehicle with the stock discs + drums setup I'd suggest most folks don't need that level of "performance". I did manage to overheat the (very old) brake fluid on the ambulance snaking down Col d'Petit St Bernard but that's a 3 ton truck and it's a very steep & twisty road even by alpine standards, it's never happened before or since even towing 3 tonnes or driving other notorious alpine roads around Europe. Quote Link to comment Share on other sites More sharing options...
L19MUD Posted August 29, 2023 Share Posted August 29, 2023 41 minutes ago, FridgeFreezer said: Worth noting that vented/grooved/drilled discs don't stop you any better than solid discs - they just let you do more hard braking before they overheat. Unless you're boiling your brake fluid on a regular basis there's no benefit at all in buying flashy discs, especially on the rears. Given how hard it is to boil the brakes even on a heavily laden vehicle with the stock discs + drums setup I'd suggest most folks don't need that level of "performance". I did manage to overheat the (very old) brake fluid on the ambulance snaking down Col d'Petit St Bernard but that's a 3 ton truck and it's a very steep & twisty road even by alpine standards, it's never happened before or since even towing 3 tonnes or driving other notorious alpine roads around Europe. It also reduces the risk of overheating and warping the discs. Totally agree on the rears of a Land Rover though, you will never get them that hot 1 Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted August 29, 2023 Share Posted August 29, 2023 1 hour ago, L19MUD said: It also reduces the risk of overheating and warping the discs. Totally agree on the rears of a Land Rover though, you will never get them that hot I'm a little on Carrol Smith's side on the whole warped disc thing... https://www.brakes-shop.com/brakepedia/general/myths-of-the-braking-system In that stuff that gets blamed on warped discs almost never actually is a warped disc. Quote Link to comment Share on other sites More sharing options...
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