Can i use 75w90 for transmission?

Daaan · 08-26-2008, 01:48 PM

No store around me sells the specified 75w85 gear oil for my transmition. The dealership says it will take 5-6 business days, and will cost $47 a quart with a minimum order of 3 quarts!(almost $150)

Every performance shop around me has both synthetic and non synthetic 75w90 for $8 a quart. Can i use 75w90 in my transaxle?
thanks for the help

propeine · 08-26-2008, 02:11 PM

None of the performance shops carry redline or royal purple?

Daaan · 08-26-2008, 02:42 PM

Quote:

Originally Posted by propeine

None of the performance shops carry redline or royal purple?

They carry royal purple but there wasn't a 75w85, only the 75w90.

propeine · 08-26-2008, 03:16 PM

I'd be looking for royal purple syncromax. I would say see if you can't find a vendor to ship to you up there in Canada. Summitracing carries redline products and I'm sure they ship up there. I'd rather wait a few days than ruin a trans.

Splitpi · 08-26-2008, 04:21 PM

GL4 only..

Daaan · 08-26-2008, 04:41 PM

thanks for the advice. But would it really hurt the tranny only 5w over?

propeine · 08-26-2008, 04:49 PM

Probably be fine as long as its GL-4 and not GL-5 but I don't want to be the one to tell you to do it and have you frag your trans.

Moparbishi · 08-26-2008, 08:41 PM

2g recomends 75w90. It should be just fine in a 1g I would think.

Daaan · 08-27-2008, 03:06 PM

Alright thanks everyone, im going to try it this weekend.

50trimmed1g · 08-27-2008, 03:38 PM

Like stated before, make sure it is safe for yellow metals. Gl4 only.

Freerevving · 08-27-2008, 03:57 PM

yeah sorry royal purple is GL-5

anything that says "meets requirements for GL3, GL4, GL5" is really just a GL5 gear oil

With 99% of the GL5's you will have long term problems with synchro engagement, because the oil is too slippery

brownfinger · 08-27-2008, 05:13 PM

I'm currently 'trying" pennzoil synchromesh fluid, via autozone. I'm running an original trans w/212,000 mi. I googled something like "pennzoil synchromesh" or "do I need a new transmission?" and half of first page of the results were direct links to various dsm sites! The consensus seems to be that we don't really need new transmissions, just synchromesh oil. My 93 eclipse has been reluctant to go quietly into the dark night that is second gear since , oh, 1995. When it started bitching about 1st and third, I tried the synchromesh. I think they should have specified that stuff in the first place, even though it probably wasn't around then. The recomendation I read said to change it out at shorter intervals the first few times, every few 1000 miles or so. I think this was just to make sure that the old and new fluids aren't mixed together. I haven't done that yet, but so far all is well, better than ever, and it's been at least 6 months, maybe more, and it's a daily driver.

soldave · 08-27-2008, 08:29 PM

Sorry to threadjack slightly, but you guys are saying that the Royal Purple Max Gear 75W90 rated transmission oil would not be good for an AWD DSM as it says it passes GL5 standards too?

Freerevving · 08-27-2008, 08:52 PM

that's right...

They're only trying to get you to buy the oil... GL5 is not a standard of quality... it's a level telling you the co-efficient of friction... in other words "too slippery"

GL4 catches the synchros just right and is made for our transmissions. GL5 builds a film and eventually (if not immediately) makes the sychros slip (grinding). GL5 is for RWD transmissions.

You can buy generic GL4 and it will fix the problem just as well as Redline MTL or Pennzoil Synchromesh... You can rarely find it on the shelf, you might have to ask them to look for it on the computer. The only problem with the mineral-based GL4 is that it's full of sulfur and needs constant changing.

I have purchased 2 AWD DSM's that had grinding transmissions... and they both stopped grinding with generic GL4... after knowing what the problem is, I switch over to Redline. I have actually cured several transmssions in the past simply by switching to GL4.

The good thing about using Redline or BG is that they're fully synthetic and never need changing.

soldave · 08-27-2008, 09:07 PM

Thanks for that. Will have to look around. I know the Japanese shops will only sell Japanese oil and that is hugely expensive (at least $25 a quart on average) but will see what I can come up with.

So what is the difference between a GL-4 oil and a GL4-5 oil (and while we're at it, a GL-5 and a GL4-5 oil)?

dsm-onster · 08-27-2008, 09:12 PM

I noticed the same thing after swapping to generic gl-4 as a quick fix to get my wife to work. Go fugure, she drives my holset powered dsm. . . but any way. I didn't change the oil that often, and it started grinding a little again. I pulled the tranny for a clutch swap and in with the new generic oil and the grinding when away. . . So the generic oil needs to be swapped out more? This would explain my situation. . .

Freerevving · 08-27-2008, 09:49 PM

yeah there's sulfur in the oil, which is very slippery, but there's a counter-acting chemical to the sulfur that also protects it from corroding the gears... the counter-acting chemical wears out quickly, this is why Mitsubishi recommends you change the oil every 10k miles. It's bad to use it (mineral-based GL5 is even worse) because it slowly eats away at your synchros.

I believe the DSM gear oil Mitsubishi sells is a sythetic GL4

EDit: just looked up GL4/5... I'm not sure, but I think it's a GL-5 that's claiming it's rated for both, I know they're using it in some Audi's and some owners say that it's wrong and should be using GL4

soldave · 08-27-2008, 11:36 PM

Spectacular. Done some research and it seems like pretty much the only gear oil we can get here in the whole of Okinawa is GL4 or the GL4-5 Royal Purple stuff I've been using. Guess I'll have to keep on going with that for now

CameronF · 08-27-2008, 11:45 PM

my 1g manual recomends API GL-5 SAE 75W-85W gear lubricant, but i should really be using GL-4?

Freerevving · 08-28-2008, 02:10 AM

Quote:

Originally Posted by soldave

Spectacular. Done some research and it seems like pretty much the only gear oil we can get here in the whole of Okinawa is GL4 or the GL4-5 Royal Purple stuff I've been using. Guess I'll have to keep on going with that for now

Nani Ka osagashi Desuka?

lol I only know a few phrases... But I can tell you what I would do, if I were there

Japan is filled with FWD cars that require GL-4... try the dealership or autoparts store... You might have a hard time finding something online.

Now, are you saying that you did find the GL4?

soldave · 08-28-2008, 02:23 AM

Nope. Didn't find it. I called Autobacs, which is the main chain of general Auto parts stores and they only had GL-5 rated oils. I have found one place with GL-4 rated oil but it's just under $30 a quart as it's non-Japanese.

The hunt will continue. Don't really want to get crappy oil though just for the sake of it being GL-4.

Freerevving · 08-28-2008, 02:30 AM

well I'm sure mitsubishi has something.... should cost less (compared to what you pay for stuff lol) over there

Maybe they don't use the GL ratings? try some FWD toyota/honda oil or just call mitsubishi

also try to find out who sells redline