Thread: LT95 overdrive

Only ever used engine oil in my RRC with LT95 & overdrive.

Haven't had any problems, so haven't tried anything else.

I have had an O/D on my 101 for three years now and had absolutely no issues with it. I run engine oil in the tfr/o/d unit. When changing down I nurse the synchros in the O/d by double shuffling but it will change OK without doing it - just that parts are getting hard to find and it helps save the synchros. Als0 - even though the manual says you can do it I do not drive in third gear with O/D in - again just saving wear and tear on what is becoming a rare piece of kit for parts.

When filling I do the O/d and tfr at the same time. I remove the O/d and tfr fillers and fill through the O/d filler until the oil comes out the tfr filler - that way both are at the correct level in one easy operation.

Cheers

Garry

Originally Posted by garrycol

I have had an O/D on my 101 for three years now and had absolutely no issues with it. I run engine oil in the tfr/o/d unit. When changing down I nurse the synchros in the O/d by double shuffling but it will change OK without doing it - just that parts are getting hard to find and it helps save the synchros. Als0 - even though the manual says you can do it I do not drive in third gear with O/D in - again just saving wear and tear on what is becoming a rare piece of kit for parts.

When filling I do the O/d and tfr at the same time. I remove the O/d and tfr fillers and fill through the O/d filler until the oil comes out the tfr filler - that way both are at the correct level in one easy operation.

Cheers

Garry

Hi Garry,

In your opinion, will the OD cope with an Isuzu Turbo in a 110? A 101 is quite a heavy and hard working vehicle so I would assume if after 3 years you have had no issues, it is up to the task. I would obviously have to use it only in top gear, and no towing but it is a tempting proposition. I guess the only problem is getting one

I have no experience whatsoever with the LT95 version, apparently way stronger than the Series ones...

JC

I cannot answer the question directly - I do recall past posts where people have said that based on their experience the o/d will not last behind an Isuzu but then along came a couple of posters who said that they had them in their Isuzus and they had lasted (but not turbos).

As I understand the Isuzu engine, for its size it is not all that powerful and only moderately torquey but it is the torque pulses from having four cylinders and a not overly heavy flywheel to dampen them (Isuzu experts come in here). The V8 has far more power and I assume a bit less torque (certainly developed at higher revs than the Isuzu) but all is developed much smoother.

So I would say that if you drove a turbo Isuzu with egg shells under your accelerator foot you might get away with it, but diesels have a habit of lugging at low revs in higher gears sending torque pulses through the system and that is when the O/D would break.

Would I try it? For sure (using a sacrificial O/D) but I would make sure you carried the original tfr gears etc with you to pull it out if it broke. On long trips I do, but as I said I have had not any issues (I have not towed anything heavy) and most people I know have not had issues.

Sorry I cannot be more definite - I am sure the Isuzu people will be along - hopefully someone who has actually got one on their Isuzu.

Yes the Lt95 O/d is far surperior to the series - same basic design but better lubrication and heat dispersion.

Cheers

Garry

Thanks Garry, yes it is the torque pulses that destroy everything in their path I have gone through 4 transmissions as a result However, just using it for non lugging highway use I can see it lasting for a bit, surely.

I'll look around and see whats about...

JC

I would pm Rick 130 about this or put it in general tech. Old versions of EP 90 corrode the brass shims in the gearbox of an LT95 like mad, not sure about the spacers, etc in an LT95 TC.

Oil can migrate between the LT95 GB and TC under certain (normal wear) circumstances.

Apparently newer versions of EP 90 don't have this corrosive effect but I don't have the knowledge. Ask wider.

cheers, DL

looks like engine oil it is then.thanks everyone

wasnt there someone that piped up that they had an overdrive behind a 4bd1 for ages without issues.