sparg

Well, here we are, all these years later older and, er... wiser(?) Replaced that other vibrating td5 90 (which eventually was nicked off my drive) with a later, cleaner, whiter doublecab 110. Been jolly good, had two trips to Spain (which the wife says she never needs to do again) and so o. All went well 'till the ECU exploded (£600+!!) but now, with a weird sense of deja vu, this morning I heard just the hint of a 'twitter' - sounded as though from engine bay, but a little later, accelerating in 5th uphill, about 50-60 - a deep, slight vibration. Sounds like UJs, so dived in to a friendly LR chap's garage (I was wearing smart clothes) - but he couldn't find any play in them. I haven't given up on that idea, though - have to wait for it to develop. But, my question: if not UJs, what else?

out of interest, why not old oil?

yep, that's the one I've been using. But see earlier postings about the possibilities that some additives contain contaminants whose long term effects may not be known. I should say that I'm still experimenting with 2-stroke oil - it seems to make my engine smoother, but I haven't yet experimented with varying the quantity to find the best cost/benefit relationship. I've been cautiously using 250 ml per 70L tank. Whether I could have similar results cheaper by using old engine oil (from my own car) I don't know yet. If anyone else is thinking of carrying out experiments - I've been quite experimentally 'sloppy' - really, to have anything scientifically valid, one has to be quite rigorous and objective about test procedures. It's hard to escape the possibility that one gets the result one hoped for - people subconsciously drive more cautiously when they are looking for an economic miracle. So, I'm going to embark on a long term test over 5K miles (10 weeks) driven over the same route (my daily round trip to work is 95 miles approx) to iron out variations. I will not be able to compare this to 'before additives', since I didn't, if you see what I mean. If I had, i would have been able to separate the results (if any) of the "injector cleaning" function of the additive from the improved cetane effect. However, I can say that, prior to additives, I covered more than 5K miles in the 110 doublecab TD5, and averaged just under 27 mpg, so I'll be using that as my benchmark. So, if anyone else covers fairly substantial mileage in a defender of whatever type, and are thinking of testing, can I encourage you to be more rigorous than I've been in in objectively documenting 'before and after' phases of the experiment? keep an exact record of mileage, fuel receipts and amounts of additive used at every stage; you can't argue with real, hard data. After all, if my rather haphazard experiments seem to indicate a 10% improvement in economy (and some unquantified improvement in engine usability), that's a real result and worth telling people about

Update: I'm still using additive alternate weeks/ tankfuls, and consistently averaging 31.6 mpg in a 110 double cab pickup, TD5, 130K on clock. I also use 2-stroke sparingly - about 2-300 ml per 70 litre fillup - not really more power as such, but smooth revving ( I find a slightly harsh vibration under acceleration in higher rev range; no rev counter, so I don't really know what 50mph in 4th is). The millers definitely smooths out the power at the bottom end - it will quite happily pull from below 30 in 5th (though not with breakneck acceleration) whereas before, I had to change down to accelerate to avaoid that kangaroo effect. An unexpected result: cornering is better! - that is, dry country roads, 40-60mph, up and down speeds, the improved torque seems to translate into more surefooted planting on the road - and without being up and down the box.

I notice the Mudstuff handles are screwed onto the underside of the gutter - are these into the headlining fitting holes - are they already threaded? - I ask because: a) I'm lazy and don't want to pull the headlining down, and b) I'd like to use those holes (if they are threaded) to mount bars in my doublecab, to clamp small speaker units on. Given the high noisefloor in a defender, and the shortage of good speaker mounting points, the best way to have good quality sound without causing hearing damage is to use small HF speakers near head level. There are various psychoacoustic reasons for this (don't ask), and I'm experimenting with possible solutions. Flat panel distributed mode loudspeakers (DMLs) attached right across the headlining can work, but the solution is expensive since dmls have relatively poor sound pressure levels (SPLs) and so you need a lot of them. So, piston drivers (conventional speakers) and high level mountings (attached where you'd put grab handles) would be good. The aim is clarity, not bleeding ears.

Hi all I had thought that it might be wise to use additives sparingly. The results I've had over 2 tankfuls, just under 900 miles, - 31.266 mpg. I've said before that, short of cruising at a steady 50 mph all day, the sort of mileage I do is probably the gentlest sort - not slow, but the majority of the journey is between 30 and 60, only about 15 stop /give way junctions (though I certainly use the accelerator appropriately). It's a double cab p/up 110 td5 with 120K on clock. Unfortunately, I don't have quite as precise figures for consumption on the same roads without additive. However, I do now when I had to fill up, and I'm certainly getting an extra 40 miles (conservative estimate) per tank, and my estimated consumption was 27 mpg. that would mean better than 15% improvement! Next, I want to try a Bearmach tuning module I've just agreed to buy, to see if it gives me a similar power/torque performance. In the meantime, if I can bear to go back to the old sluggish setup for a tankful, I should try to draw some more precise figures for the non-additive state.

Just had it suggested (over on Landyzone) that it could conceivably be that I previously had poor compression (rings or valves) and the improved cetane ratig has compensated for it. That might imply that a healthy engine wouldn't see the gains I'd made, which kind of make sense. initial back-of-the-envelope calculations conservatively show an improved economy of 10% - but I'm skeptical, since if it was that easy, everyone would be doing it. To put figures on that, for countryside driving - accelerating and decelerating, up and down the box, rarely stopped, rarely high speed cruising - topping out occasionally at 70, usually in the 40-60 range, - I usually get 26-27 mpg out of a 110 doublecab td5. This last 440 miles, I've had what seems to be 33 mpg! - that difference can't be right. I need a much better set of figures, and even so, the explanation is more likely to be that I haven't (for the last 20K miles) been getting the performance I should have been. This is much more likely than the idea that I've stumbled across some 'magic formula'! I'll collect better figures and post them

Yeah - what I can't get my head around is why I might have been having this flat spot problem in the first place. I'd even wondered if it was a pedal mapping problem, or was it just that the td5 engine is inherently not very torque-y below the turbo range, and that couple with the 110 being heavier than my previous 90. However, now it's like I have a different turbo fitted! Of course, all this doesn't explain why the performance gains fall away at higher revs...

Well, I decided to experiment, and not put additive into the next tank full. I got about 10 miles, and in exasperation, stopped and put a 50ml treatment in again. The old lethargy at low revs was back. I had to work the box to get up to speed. After the treatment, about a couple of miles along the road, the new low end pulling power had returned. At varying speeds, between 35-40mph and and 60+ mph, it was like driving an automatic. So the effect is certainly not down to 'cleaner operation' (which, according to the instructions, should ensue after about 200 miles - but I had done 400), so must be down to increased cetane rating.. So it looks as though a £90 fillup needs a £2.50 shot of additive to run nicely. The question is: do I actually make that up in increased fuel economy? My next task is to measure, with and without, a tankful each time, taking the same journey each day. Will post result in a couple of weeks.

I notice this thread seems too old to resurface. Still, I'm now going to try a fill up without additive, to see if the low-end flat spot returns

know this crops up every now and then, but hadn't expected that, on adding the appropriate measure of millars (2003 td5 110 with 100K on) because I thought cleaning the injectors a bit might be a good idea (how do these cleaner reckon to work?) I was suprised by an instant improvement in low-end performance. Clearly, the additive is raising the cetane rating. I'm finding that the slight hesitation at low revs, when changing gear or setting off is removed. The vehicle now accelerates quite happily from 30mph in 5th (on the flat) - I always had to change to 4th to do that. I'm also finding improved fuel economy - quite definitely, though I haven't precisely measured - but travel same route every day and know from experience where the fuel guage will be after each 50mile journey. This improvement is very likely down to a drastic reduction in gear changes on corners and hills. What I'm not finding is any improvement in revving - and that might be down to something else (binding wastegate actuator, mucky MAF, atc) - the vehicle was always 'reluctant' to rev - it 'wants' to change out of 3rd at 30mph, out of 4th at 40-45 mph, and, whilst now blissfully quiet at 50 -55mph, the engie noise gets a bit thrashy at 60-65. IN fact, given a long enough airfield, it will actually climb through 75 upto 80+ (on the clock) but it's bloody noisy. So now, with the improved bottom end, it has a power band that is usable, but still narrower than (I feel) reasonable. My old 2002 '90 that was prematurely 'recycled' by we_pike_anycar.com was more willing - though it had no cat +straightthru centre pipe. You could hear the turbo whistle for miles - I can't hear my current one at all (though it must be working, or it would never reach 70, I'm sure) So I'm thinking that the additive is working at the moment, not because of cleaning but through increased cetane rating, but this has more effect at low revs and the advantage is neutralised at higher revs by the engine's inability to take advantage of it I wonder if a boost gauge could tell me more?

Yeah, see your point - a harder spring might thump slightly more, but resist being 'thrown' by the rapid 'lentghten-compression' cycle that a pothole induces. The pro comp shocks don't help, I think

I should just say that I haven't managed to try it on a right-hande with appropriately placed pothole - I just haven't found one. BUT... on a left-hander with a pothole hitting the right wheel, theings aren't neraly so bad. This could point to the left suspension (that traditionally takes more hammer on British roads), OR that anyhow, the behaviour on the suspension under load differs from that when it's unloaded As it is, I simply couldn't imagine how a defender such as mine could possibly handle more power - it would leap into a field!

I thing panhard rod bushes would be a good thing to do, even though it's not particularly wander-y. revisiting this issue of dampers seems to be a good idea. A further observation about this 'axle bounce' thing: I notice that it's when the inside wheel (well, so far, that's been the left wheel) on a corner hits a significant pothole. That is, the suspension on that side is unloaded somewhat, then the wheel 'falls down' the hol, then swiftly is thrown up, at 50mph. The result is that the axle makes 4 bounces (well, 3 + original impact) successively diminishing. It being a beam axle, the whell that is loaded (the 'outside' wheel on the corner) is also affected. Hence, the vehicle 'tramps' outward on the corner. When one thinks about it, this double stimulus (down then rap[idly up) has to be the hardest challeng for a suspension with so much unsprung weight.. The fact that it occurs at the 'drooping' end of the axle might also have something to do with it? In that case, might an anti-roll bar help by reducing that 'droop?

Hmm - don't think I can see such brackets, It's not really the steering jumping - it's the vehicle jumping...