PistonHeads.com Forum

Gearbox oil



Original Poster:

16 posts

90 months

Tuesday 21st August 2012
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I am the proud owner of a 1987(D) Lotus Esprit HC (normally aspirated), which I have had for over 3 years now. I have tried to 'keep on top' of all the usual little niggles and have also tried a few upgrades too. I thought I would share what I consider to be a very worthwhile and simple upgrade.

As most of you will know the Citroen gearbox on the Esprit is not it's strongest feature! It is not known for having a slick gear-change and by all accounts is the near the limit of its torque handling capabilities at the fairly modest power output of even the turbo models. On top of this they are incredibly rare, and therefore expensive to replace.

With the all the above in mind I considered that changing the gearbox oil was a priority and also thought that the type of oil used might make a worthwhile difference too.

When I first got the car I was not impressed with the quality of the gear-change, although I was expecting as much from all the road tests I had read. Somewhat more alarmingly I would regularly hear (and feel) a 'crunch' when changing down into second gear. I'm not talking about just 'slamming' it in there either, but what I considered to be a fairly lazy down-change with a blip of throttle to match the revs to the road speed.

After a bit of research I opted for Castrol TAF-X, which appeared to get good write-ups and, I believe, is even endorsed by the factory. This made quite a difference to the gear-change, a lot slicker, but still crunching into second gear. I don't know what oil was in the gearbox (or how old it was) when I bought it, so maybe not a fair comparison.

This year, after two trips to Le Mans and also a few spirited laps of the Nurburgring in the intervening three years, I thought it wouldn't hurt to change the gearbox oil again.

On the advice of Mike at Lakeside Engineering we decided to put Carplan 75W90 semi-synthetic gearbox oil in the gearbox. I have to say I was dubious - Carplan? Isn't that the cheapo rubbish that cheapskates put in their old bangers?! Mike assured me that it wasn't and I was finally convinced when he told me that he had put it in the gearbox of his own Porsche 911(996) and that it had transformed it.

Well, what more can I say? The gearbox of the Esprit has been transformed! The change is much slicker and no more crunching in to second gear. It's not even that expensive, either, at about £8 per litre...


14 posts

108 months

Wednesday 22nd August 2012
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I am not an engineer at all but would be interested in hearing any comments as the Esprit has more than a gearbox and TRANSAXLE oils have usually been specified by Lotus.
Might not matter as the oils may be similar but could have longer term difficulties.
I recently changed my V8 transaxle oil (Renault gearbox of course) for Castrol Syntrans Transaxle 75W-90.


935 posts

181 months

Thursday 23rd August 2012
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I too have recently changed to Syntrans and the gear change has noticable got better especially when cold!


David Walters