Gearbox oil

[Jon S]

Hi

I ve had my 350i for about 6 months now, but have only recently found this site. I ve picked up some useful info from your threads but haven t posted anything yet - so here s my first post.

While using my car over winter I ve noticed its really difficult to get 2nd gear when the car is cold. I m thinking of changing the gearbox oil and might put synthetic or semi synthetic oil in the gearbox to help the problem. Has anyone tried this, is it a good idea or should I stick with the normal gearbox oil? Do you recommend any particular type of synthetic oil.

Also is there a drain plug to get the old oil out or do I have to syphon it out?

Thanks

JS

[badredwedge]

Welcome to the mad house Jon.

Are you going to BBWF in July ?? its a must for all Wedgers.

Drain Plug, sure there should be on under there somewhere

Oil I only ever use standard AT oil, but others on here may have a better idea

Are you sure its not your gear linkage, loose. worn etc.

Once again welcome, well done and good luck

[wedg1e]

The LT77 'box has a built-in oil pump; it's a bit fussy about the oil you use - the usual recommendation is actually automatic transmission fluid (ATF).
It's also a well-known characteristic of the LT77 that it doesn't like to be hurried at the best of times; probably not the ideal gearbox for a sports car but then I suppose the idea is that you use the torque of the V8 rather than lots of frantic cog-swapping.
Given the cost of gearbox rebuilds I'd be a bit wary about experimenting, but if you find something that works, we're all ears

[Jon S]

Thanks for your replies, I ll probably stick to ATF. Don t want to mess anything up, I ll check the linkage whilst I m under there doing the oil though.

I m on holiday when BBWF is on. I ll have to be better organised next year!!

Thanks for your advice.

JS

[andymadmak]

Do not use the ATF fluid! Use a decent SAE 75/80 gear oil.
This info came to me direct from the man who designed the gearbox for Rover.
All the racing SD1s used Motul gear oil and not ATF fluid.
The ATF fluid was only used because some customers complained that their SD1s would not
change gear cleanly on a cold morning. The ATF fluid - being much thinner was selected as a quick fix, and was only tested by the ladies in the staff canteen at Rover Solihull.
If you can put up with a slightly baulky change when cold then a fully synthetic SAE 75/80 will give you a lovely
change plus the box will last a lot longer

Andy

>> Edited by andymadmak on Wednesday 5th April 13:30

>> Edited by andymadmak on Wednesday 5th April 13:32

[350matt]

Go for the semi-synthetic 75-90W stuff from castrol
Made a big difference in mine

Matt

[dickymint]

RPI say this.............................

'What did Rover do to help?

As this gearbox evolved, Rover made a few modifications, none of which cured the problems. The 'D' suffix box is by far the strongest, but as strength was not the problem this seemed a little inappropriate to us. Also, they changed their mind three times as to what Transmission Oil to use. In the first instance it was [I believe] EP80 (or perhaps 90) but this transmission oil is very thick when cold and did not allow easy selection of 2nd or 3rd gear until the transmission was warmer.

The second recommendation was Castrol TQF. This was far better for the gear changes, however, as it is an auto transmission fluid some problems were encountered with its lubrication qualities and many gearboxes failed.

The third recommendation (and I have heard of none since) was to use Castrol SMX, although I believe this is, in fact, still an auto fluid, it is a synthetic fluid. We have been recommending this ourselves over the past 7 or 8 years and I have had no bad findings on its use.'

www.rpiv8.com/transmission-3.htm

[wedg1e]

So there you have it. It's ATF or it isn't, depending on who you speak to.

[number 7]

wedg1e said:

So there you have it. It's ATF or it isn't, depending on who you speak to.

Or you can use engine oil. Mines running Mobil 1 5-50, only because I had some left after swapping to Motul. As long as the oil you use doesn't have EP additives. The Rover box doesn't need them, and it attacks the syncros I think.

7.

[leorest]

So do you know more or less than you did to start with? I'm not sure what I'd use if I was changing oil now! There certainly seems to be plenty of pros and cons to each option. I guess it's horses for courses.

Welcome indeed to the Big Bad Mad House. I'm sure you'll find this forum invaluable for all things Wedgie and even a few things in the garden too.
Leo

[Jon S]

I m glad thats clear then!

Thanks for all your posts, I ll have a think about it. May try the semi synthetic and see if it makes any difference, if not change it back to ATF.

I ll let you know how I get on.

Jon

[andymadmak]

Seriously, the ATF route is a bad one. Ken Tomlinson was the man who designed the transmission for Rover
back in the early 1970s. Ken is retired now, but still runs a little specialist rebuilders called N+T transmissions, based at Over Whitacre near Birmingham. He can tell you all about how the box came into being, and why they used ATF fluid from early in the production cycle. (as per my previous post)
Ken says that most transmissions run on ATF in high torque usage will fail prematurely and most of those will not be worth the effort of rebuilding because the wear is so great. The racing Rovers used SAE 75 / 80 gear oil by Motul. I use the Catrol synthetic equivelant (SMX or SMS, can't remember) and the change is fine except for the first few miles on the very coldest mornings, and even ten it's really only the 1st - 2nd change thats a bit sticky. TVR did not use ATF fluid when they used the gear box - the handbook says to use SS80.

Andy



>> Edited by andymadmak on Friday 7th April 10:14

[jmorgan]

My fluid was changed out from ATF to sommit synthetic in a silver bottle. Cranky when cold but a lot smoother when warm. Sort of when the box is warm, the engine is warm as well. Hooning time.

[SLB]

Don't listen to this Dickymint, but my old SEAC had ATF fluid in it when I got it. I changed the fluid when I changed the exhaust at 30k miles and there was heap of metal filings on the magnet attached to the drain plug. Heard the same comments from people in the club and elected to change to semi synthetic 75 grade. Due to the seals weeping at the back, at 40k miles changed to 80 grade and used some of that seal revitaliser and noise reducer, which did a really good job.

I used a brake bleed kit to re-fill it each time, time consuming and a pain but it worked.

[adam quantrill]

I find the 75W a bit thick on cold mornings and the ATF too thin when hot. I've taken to using a cocktail of the two, which seems to give the best of both worlds. Roughtly 1/3 ATF.

I do get through gearboxes anyway but I haven't noticed this mixture making them last any less miles.

- Adam

[wedg1e]

adam quantrill said:

I do get through gearboxes anyway - Adam

[digga951]

I asked the Opieoils chap on the General TVR forum which lubricants were specified for the V8 Wedges and he replied with the following:-

----

Here is what our database says for this model:

TVR 1984-89 Petrol 350i, 390 SE, 400 SE
Engine 5W-50, 10w-50 4.6litres
Manual Transmission ATF-D2 1.6litres
Automatic Transmission ATF-D2 7litres
Differential LS 90 1.4litres
Power Steering ATF-D2 -litres
Brake and Clutch Fluid DOT 4 -litres

This is all the info that I have, hope it helps.

Cheers
Simon

-----

I've been doing lots of research on various Rover, Jaguar and TVR forums on the net and there certainly seems to be a mixed idea of what is best. ATF gearbox oil is recommended by some but hated by others, some say 5w40 fully synth for the engine is essential, some say 20w50 mineral will be just as good considering the age and design of the block. Some say fully synth diff oil is needed, others say avoid it as it will rot the seals and recommend mineral based. So much conflicting information! Does no one actually have a definate answer as to what is best? If everyone is happily using different conflicting products without any problem, then are there more myths than facts flying around about what is or is not best?

For what its worth, here is what I have just ordered after much research:-

Engine oil - Motul 15w50 semi synthetic
Gearbox oil - Castrol SMX-S fully Synthetic 75/85
LSD Diff oil - Silkolene BOA 90 LS Mineral

I'll let you know the results as and when things either break or run smoothly! :-)

Dan.

[number 7]

digga951 said:

I asked the Opieoils chap on the General TVR forum which lubricants were specified for the V8 Wedges and he replied with the following:- ---- Here is what our database says for this model: TVR 1984-89 Petrol 350i, 390 SE, 400 SE Engine 5W-50, 10w-50 4.6litres Manual Transmission ATF-D2 1.6litres Automatic Transmission ATF-D2 7litres Differential LS 90 1.4litres Power Steering ATF-D2 -litres Brake and Clutch Fluid DOT 4 -litres This is all the info that I have, hope it helps. Cheers Simon ----- I've been doing lots of research on various Rover, Jaguar and TVR forums on the net and there certainly seems to be a mixed idea of what is best. ATF gearbox oil is recommended by some but hated by others, some say 5w40 fully synth for the engine is essential, some say 20w50 mineral will be just as good considering the age and design of the block. Some say fully synth diff oil is needed, others say avoid it as it will rot the seals and recommend mineral based. So much conflicting information! Does no one actually have a definate answer as to what is best? If everyone is happily using different conflicting products without any problem, then are there more myths than facts flying around about what is or is not best? For what its worth, here is what I have just ordered after much research:- Engine oil - Motul 15w50 semi synthetic Gearbox oil - Castrol SMX-S fully Synthetic 75/85 LSD Diff oil - Silkolene BOA 90 LS Mineral I'll let you know the results as and when things either break or run smoothly! :-) Dan.

I think Opie are a little out with their info: the engine should take c. 5.5l, especially if you've got a cooler, which the 400/450 should have. And my '89 400 handbook specifies SS80 for the gearbox (not that I use that). I've used both SMX and the Silkolene LS in the past, and would do so again. As for the engine, Opie usually suggest 300V, which is what I run, and is fully synth. Which Motul have they suggested for you?

7.

[dickymint]

Dare I say this! but most Wedgers do not run there cars in the cold (and i mean in the COLD not 10 AM on a chilly Sunday morning), So they do not experience the stiff gearchange. I doubt if there will ever be a definative lubricant for us, so use what suits your driving habits.

[digga951]

[quote] Which Motul have they suggested for you? [/quote]

The 300v is the stuff they have quoted someone on the other forum, however I got some of the 3100 15w50 semi synth very cheaply in a French supermarket. I have 150,000 miles now so I'm doubting that top spec oil would really be necessary in my car. I'm going to try it and see what happens.