Santiago Posted September 27, 2011 Share Posted September 27, 2011 The question is for those with experience using a Roverdrive overdrive (the mechanical Canadian units) in a D110. Will the overdrive work well in a D110 with 33 inch tires on long trips along flat roads or will it be overgeared? My engine is a slightly tuned 2.8TGV engine. I currently run 1.22:1 Discovery gears in my transfer box with 32 inch tires (265/75/16) and it is sort of OK but I will need to use my truck in the mountains more in the future and the gearing is "too long" for that kind of terrain. I will therefore go back to the original Defender gears and probably install an overdrive for long journies on flat roads but the question is: can I go to 33 inch tires (285/75/16) or will it be too much for when using the overdrive? Your opinions will be much appreciated. Cheers SANTIAGO Quote Link to comment Share on other sites More sharing options...
western Posted September 27, 2011 Share Posted September 27, 2011 With a 1.22 transfer box & the overdrive I reckon it'll be way over geared, my 110 runs 255/85 tyres & the standard 1.41 TB & a GKN overdrive it works fine on all roads, doubt you'd get into OD on mountain climbs, never even thought about engaging OD in mine while climbing big hills. Quote Link to comment Share on other sites More sharing options...
Santiago Posted September 27, 2011 Author Share Posted September 27, 2011 With a 1.22 transfer box & the overdrive I reckon it'll be way over geared, my 110 runs 255/85 tyres & the standard 1.41 TB & a GKN overdrive it works fine on all roads, doubt you'd get into OD on mountain climbs, never even thought about engaging OD in mine while climbing big hills. Hi wetsern Thanks for the reply, However there is some confusion: a) I am planning on going back to my Defender transfer gear ratio (1.4 to 1) and installing an overdrive while changing to 33 inch tires. b) I am not planning on using the overdrive while going up the mountains. I am planning on using it while driving on the flats. Overall I will eventually end up with a similar situation as you have (33 inch tires, 1.4 to 1 transfer ratio and overdrive). Do you use overdrive often while on the road? Can you hold it for long intervals? Thaks Stgo Quote Link to comment Share on other sites More sharing options...
western Posted September 27, 2011 Share Posted September 27, 2011 I my GKN OD as much as possible, it drives very well on long trips, motorway is almost all done with the OD engaged, also I use it a a split gear as well, normal motorway cruise is around 60/65mph with the rev counter showing about 2100rpm. Quote Link to comment Share on other sites More sharing options...
Santiago Posted September 28, 2011 Author Share Posted September 28, 2011 Thank you Western. It is useful data for me. By the way, which engine do you have? Quote Link to comment Share on other sites More sharing options...
Snagger Posted September 28, 2011 Share Posted September 28, 2011 A Roverdrive gives a 28% gearing increase, while the 1.22 LT230 is geared roughly 15% taller than the standard 1.4 ratio unit. Of course, the beauty of an overdrive is that it is selectable, so if you find it overgeared on shallow climbs with those tyres, you can de-select it and just use it for flat or shallow descents. As mentioned, it will also work well as a gear splitter, giving you a higher 4th gear when 5th is just a little too tall (and the same for other gears too). The Roverdrive is a very robust unit; just make sure you keep the transfer oil level correct and replace the oil on schedule and it'll serve you well. Quote Link to comment Share on other sites More sharing options...
landroversforever Posted September 28, 2011 Share Posted September 28, 2011 Ralph has a 200tdi (IIRC)! Quote Link to comment Share on other sites More sharing options...
Santiago Posted September 28, 2011 Author Share Posted September 28, 2011 Thanks Snagger, the Roverdrive is certainly appealing. A bit expensive though. If Ralph has a 200Tdi I guess my 2.8 TGV (VNT) should be able to manage the OD. Perhaps he has tweaked it quite a bit. I seem to recall that from another post. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted September 28, 2011 Share Posted September 28, 2011 2.8TGV, 33's and an overdrive... http://www.ep90.com/index.php?id=70 http://www.ep90.com/index.php?id=88 I believe the remains of the OD are now in the back of the shed Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted September 28, 2011 Share Posted September 28, 2011 2.8TGV, 33's and an overdrive... http://www.ep90.com/index.php?id=70 http://www.ep90.com/index.php?id=88 I believe the remains of the OD are now in the back of the shed Mention of the overdrive failure on this page http://www.ep90.com/index.php?id=80 Was a GKN Quote Link to comment Share on other sites More sharing options...
Santiago Posted September 28, 2011 Author Share Posted September 28, 2011 2.8TGV, 33's and an overdrive... http://www.ep90.com/index.php?id=70 http://www.ep90.com/index.php?id=88 I believe the remains of the OD are now in the back of the shed Thanks. However after reading the story it is not clear to me that he was using 33 inch tires after installing the OD. The other thing is the unit was a GKN. I have heard many bad comments about the GKN's performance. Quote Link to comment Share on other sites More sharing options...
western Posted September 28, 2011 Share Posted September 28, 2011 Thank you Western. It is useful data for me. By the way, which engine do you have? Defender spec 200Tdi. Quote Link to comment Share on other sites More sharing options...
western Posted September 28, 2011 Share Posted September 28, 2011 Thanks Snagger, the Roverdrive is certainly appealing. A bit expensive though. If Ralph has a 200Tdi I guess my 2.8 TGV (VNT) should be able to manage the OD. Perhaps he has tweaked it quite a bit. I seem to recall that from another post. no tweaks on my engine. it's standard as LR built it. Quote Link to comment Share on other sites More sharing options...
Santiago Posted September 28, 2011 Author Share Posted September 28, 2011 no tweaks on my engine. it's standard as LR built it. Thank you. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted September 29, 2011 Share Posted September 29, 2011 Thanks. However after reading the story it is not clear to me that he was using 33 inch tires after installing the OD. I don't think TSD has run much smaller than that on the Ibex, he certainly didn't downsize after fitting the OD. Quote Link to comment Share on other sites More sharing options...
TSD Posted September 29, 2011 Share Posted September 29, 2011 I believe the remains of the OD are now in the back of the shed ... in a bucket Yes I was running 33s. I've never run anything smaller than 265/75, but any pic you see with Mach5s it was running 285/75R16 BFG MT. I could smoke the (130/HD) clutch going uphill at 80mph with the OD in. Then I tore the centre out of it. Broke the output shaft on the first R380, knackered a couple more since. Eventually the OD was sticking between engaged and not, so if you shifted it hit a false neutral with no way back. I have a 1.22 box instead now. I much prefer the OD, but it wasn't worth the hassle. I can still tow a loaded trailer without issue, so it's good enough. Occasionally tempted by the Roverdrive, but I'm not doing 110 miles a day in it anymore, so CBA to fit one, to be honest. Quote Link to comment Share on other sites More sharing options...
101sean Posted September 30, 2011 Share Posted September 30, 2011 Same here, GKN is in a bucket in a corner of the shed. Lovely while it worked but mine was very unreliable, gave up on it and fitted a disco box. Quote Link to comment Share on other sites More sharing options...
carlosbeldia Posted September 30, 2011 Share Posted September 30, 2011 Santiago, Gus, in LRTT from Spain have a TD5 with GKN unit and believe he have 285/75 R16. TD5 is 180hp Stage 2 unit, he usually goes 160kph in freeway, I think no issue at this time... Quote Link to comment Share on other sites More sharing options...
RTF Posted September 30, 2011 Share Posted September 30, 2011 Hi Santiago Have a Rover drive fitted to my 110 Td5 hard top for about a year now and can`t fault it run 265/75/16 In every day driveing leave it in high all the time only use low when starting of with the trailer and reversing I do tow a trailer with my 90 on it and still use the overdrive when in slower moving trafice just change into 4th over drive same gearing as 5th no overdrive Had though about fitting a discovery transfare box but Td5 are very high geared in first and since the 110 was bought for towing went for the overdrive Quote Link to comment Share on other sites More sharing options...
Santiago Posted October 1, 2011 Author Share Posted October 1, 2011 Santiago, Gus, in LRTT from Spain have a TD5 with GKN unit and believe he have 285/75 R16. TD5 is 180hp Stage 2 unit, he usually goes 160kph in freeway, I think no issue at this time... Thanks Carlos. I have never checked the forum from Spain, perhaps I should. Saludos Quote Link to comment Share on other sites More sharing options...
Santiago Posted October 1, 2011 Author Share Posted October 1, 2011 Hi Santiago Have a Rover drive fitted to my 110 Td5 hard top for about a year now and can`t fault it run 265/75/16 In every day driveing leave it in high all the time only use low when starting of with the trailer and reversing I do tow a trailer with my 90 on it and still use the overdrive when in slower moving trafice just change into 4th over drive same gearing as 5th no overdrive Had though about fitting a discovery transfare box but Td5 are very high geared in first and since the 110 was bought for towing went for the overdrive Thanks RTF. Isn´t he Td5 geared the same as the Tdi? At least mine is. I wouldn´t say it is high geared. Well now it is because of the Disco transfer box.... Cheers, Stgo Quote Link to comment Share on other sites More sharing options...
carlosbeldia Posted October 2, 2011 Share Posted October 2, 2011 http://www.clublandrovertt.org/index.php?topic=14050.0 http://www.clublandrovertt.org/index.php?topic=38855.0 Quote Link to comment Share on other sites More sharing options...
Santiago Posted October 2, 2011 Author Share Posted October 2, 2011 Gracias Carlos! Quote Link to comment Share on other sites More sharing options...
headhunter Posted October 3, 2011 Share Posted October 3, 2011 I run a 110 with a 2.8 TGV standard R380 and a Roverdrive O/D. Took me to Morocco and back last year heavily laden without fault. I have an AP Racing H/D clutch fitted as the standard H/D clutch slipped on hills in O/D if extra power was required without changing down. The TGV has the torque to deliver this but the clutch was not man enough, hence the change. My roverdrive has done 23000 miles so far without fault. I have fitted a roverdrive transfer box cooler plate which increases oil capacity by 1 litre, a very worthwhile mod to help keep transfer and O/D temps under control. John Quote Link to comment Share on other sites More sharing options...
Santiago Posted October 3, 2011 Author Share Posted October 3, 2011 I run a 110 with a 2.8 TGV standard R380 and a Roverdrive O/D. Took me to Morocco and back last year heavily laden without fault. I have an AP Racing H/D clutch fitted as the standard H/D clutch slipped on hills in O/D if extra power was required without changing down. The TGV has the torque to deliver this but the clutch was not man enough, hence the change. My roverdrive has done 23000 miles so far without fault. I have fitted a roverdrive transfer box cooler plate which increases oil capacity by 1 litre, a very worthwhile mod to help keep transfer and O/D temps under control. John Excellent John, sounds like you have made a very good investment in the OD. I would like to know which tires you have: 265/75/16? It is interesting I had the same problem with my original clutch after installing the Disco transfer ratio and therefore I am about to install a new HD AP Racing clutch, what a coincidence. I am glad it sounds like your AP Racing clutch is doing fine. Last question: did you notice any decrease in performance after installing the Roverdrive OD? I heard the vehicle's reaction is slower because it has to move more gears (the OD gears). Is this correct or just bull****? Cheers, Stgo Quote Link to comment Share on other sites More sharing options...
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