352 transaxle gear oil spec

[Certified Lotus]

I remember a discussion on the types of gear oil to be used in a 352 transaxle that got me to order Swepco 210 gear oil.

http://www.lotuseuropa.org/LotusForum/index.php?topic=1134.0

A friend of mine who owns a 73 Twin cam special was over to my garage and we ended up talking about transaxle gear oil. When I showed him that I installed Swepco 210 multi grade gear oil he said it was too thick plus as it met GL-5 specs it wasn’t good for my syncro’s.

I remember buying this oil specially from information from the post above, but figured I would triple check.

Anyone have additional insights?

[BDA]

I was advised by Red Line to use 75W90NS GL-5 for tranny oil. I wouldn't worry about the GL-5 spec. If the weight is good, you should be set.

[Bainford]

It has been suggested that GL5 rated gear lubes are unkind to yellow metals (brass, bronze, etc). In what way they are 'unkind' I don't know. It is a lubrication compatibility thing or do they attack yellow metals? Either way, this is the source of the notion that GL5 is not suitable for our transaxles.

There may be some wisdom to this notion, but I have often wondered if this is a case of painting all GL5 lubes with the same brush. It may be that some formulations that allow a lubricant to be given a GL5 rating are not so hard on yellow metals, especially when it comes to synthetic lubricants. I'm curious to know more about this.

[BDA]

According to the Swepco website (https://www.swepcolube.com/products/swepco-210-multi-grade-gear-lube), SWEPCO 210 Multi-Grade Gear Lube is designed for differentials and transmissions which implies that it is appropriate for transaxles. The weight, at 80W140 is a bit higher than recommended. According to this video (https://www.youtube.com/watch?v=bBhHnoA8nfc), the number you should most concern your self with is the last one (140).

[jbcollier]

First things first, ANY oil is better than no, or low, oil.  Yes, believe it or not, people have driven and ruined transmissions and rear ends because they didn't want to use the "wrong" oil.

Hypoid gear oils are designed to take the severe stresses that are induced when the centre lines of the pinion and the ring gears do not line up.  The centre line of the pinion was lowered in order to lower the floor hump in front engine/rear drive cars.

Renault transaxles have only a very slight offset of the pinion and ring centre lines.  Hypoid gear oils designed for large offsets are not required in Renault transaxles.  They will not harm the transaxle but neither are they needed.

GL5 lubricants contain additives than are "hard" on brass and bronze bushings over long periods of time.  GL4 lubricants do not have the same additives and are fine.  It was the Land Rover crowd that found this out.  We fill LR transfer cases with GL4 for this reason.  LR diffs and transmissions still get GL5.

I have filled synchromesh transmissions with GL5 gear oil, engine oil and ATF, all as specified by the manufacturer.  No wear issues with any of them.  None of them liked to be run low or dry!

Presently I am using Redline MT-90 in my Europa.  It was recommended by a long time, multiple, Europa owner on the yahoo list.  It is not a hypoid oil and is meant for manual transmissions.  It stays clean and clear showing no signs of being stressed (black and cloudy).  Most importantly it provides better shifting over the GL5 I was using before.

In my opinion, 140 gear oil is too thick.  By all means use whatever oil brand and type you prefer but use oils in the 75w90 or 80w90 range rather than 140s.

[Roger]

I understand that the damaging compounds in GL5, sulphur-based I think, are little fussed nowadays and your synchros are safe.

[rjbaren]

I recently found Sta-Lube GL -5 gear oil an my local NAPA store.  I asked if they carried a GL-4 and he ordered Sta-Lube SAE 85W90 Multi-purpose Hypoid GL-4.  Part number SL24229.  On the back of the bottle it says "Not Corrosive to copper, bronze or other non-ferrous alloy bearings and bushings".  I also used it in my trunnions.   

[Certified Lotus]

Thanks for everyone’s responses and insights. I have been using MTL  in my Elan transmission  (it’s GL4) and 75W90 I use in the differential.  I’m wondering if Red Line MTL would be good for the Europa transaxle as it is 75/W80.

[BDA]

They recommend 75W90NS (their GL-5 gear oil is formulated to work with syncros), but MTL might also be appropriate. It's worth an email to them to see what they think. There's a link on their website. I've emailed them and they are very responsive.

[jbcollier]

It will work just fine.  I run MT-90 myself.

[Pfreen]

I found this article online which discusses in detail gear oils and the difference between gl4 and gl5 oil.  https://www.widman.biz/uploads/Transaxle_oil.pdf

[BDA]

Not trying to  I thought I'd relay what I found out from the folks at Red Line Oil.

This thread and attached documents prompted me to revisit Red Line's recommendations. last night I checked the recommendations for my car (sorta): a '74 Europa Special  (there was also an option for a "Twin" and also a plain "Europa"). The only option for transmission was "U/K speed U/K U/K (U/K)." Don't ask me what they're getting at with a description like that but that seemed to imply a transmission from the UK. Hmmm... Could it be that they are making an incorrect assumption about the transmissions available in Europas?? So I thought I'd check to see what they recommended for a '83 Renault Turbo Fuego since that's what my tranny likely came from. As it turned out, they didn't make a recommendation for any oils at all for the Fuego! Yikes! Maybe the 75W90NS GL-5. I've been using is because of an error in assumption on their part. I decided to write them to see if they could clarify this situation.

Here is what I wrote:

On a Lotus Europa forum I frequent, a discussion about using  GL-4 vs GL-5 oils in the transaxle came up. I had used your car compatibility tool before and it advised using 75W90NS GL-5 in the transaxle of my '74 Lotus Europa. Then I looked a little deeper. I have a Renault Turbo Fuego transaxle (common substitution) in my car so I looked for the recommendations for a '83 Renault Turbo Fuego and there was no gear oil recommendation! Now I'm a little concerned. On the one hand, I wouldn't expect there to be much difference as far as oils go between any Lotus Europa transaxle (all made by Renault) so I might guess there is nothing to worry about, on the other hand, it makes me wonder why no gear oil was listed for the Turbo Fuego. You can see the manual for the Turbo Fuego transaxle here (http://lotus-europa.com/manuals/misc/ng.pdf). If you page down, you can see a cut-away drawing that shows the pinion has little or no offset to the crown gear in the differential. Should I switch to MT-90 which would be the more common choice for a manual transmission?
Thanks,
Jim

I got the following reply this morning:

Jim,

Thank you for contacting Red Line Oil, in your Lotus/Renault transaxle the 75W90NS would be recommended as they call for a GL-5 gear oil.

Obviously they don’t require a GL-5 gear oil as they don’t use a high offset ring and pinion and the included owners manual lists a MIL-L-2105B as being suitable, a GL-4 gear oil. Based on that and the viscosity called for, one of our GL-4 gear oils would be suitable such as the MT-85, likely providing similar viscosity at operating temperature to the original 80W. 

Sorry we don’t list all applications, but are working to update more all the time.

Regards,

Dave

Since I included a link for the NG3 transaxle manual, Dave is really replying to my situation but I suspect that all the Renault trannies are similar and thus Dave's suggestion is appropriate for all Europa trannies made by Renault.

I know this doesn't really change what has already been said on this thread but I thought it was worthwhile posting it for anybody who might desire some "official" recommendation. In fact, I might change from the 75W90NS GL-5 I've been using to MT-85 or MT-90.

[Certified Lotus]

Thanks for the update BDA. I was goi go to do same (upon your recommendation) but haven’t had a chance.

I’ve decided to use Red Line MTL  75/W80  GL4 in all my Lotus car transmissions (Elan S2, Europa TC & Elise).  Easy to have one type and all the cars will be well taken care of.