Recently drained and refilled transmission and transfer case with 90 W conventional gear lube. The transmission and transfer case now generate a great amount of noise, far more than before the lube change. Looking for suggestions on a better lube for these components. Can Lucas 85-140 Gear lube be used? We used to use Lubriplate lube on heavy machinery, anybody tried that?
1978 FJ40 Transmission lubricant questions (1 Viewer)
- Thread starter Jerryvi
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Recently changed both and used Amsoil manual transmission 75-90 synthetic. Specifically GL-4 oil. Yes, it was pricey. But I run it in my FJ Cruiser with great success and by all accounts it's a top notch oil.
People will say dump the cheapest 90w conventional oil in there and while it's true that you could use crushed Cheetos and mountain dew mix and probably be fine, my peace of mind comes from the quality oil on a 40 year old truck. Also, had small amounts of oil seeping out before the change and it's bone dry now. Shifts and runs smoother in my opinion as well.
People will say dump the cheapest 90w conventional oil in there and while it's true that you could use crushed Cheetos and mountain dew mix and probably be fine, my peace of mind comes from the quality oil on a 40 year old truck. Also, had small amounts of oil seeping out before the change and it's bone dry now. Shifts and runs smoother in my opinion as well.
- Thread starter
- #3
I hadn't tried the crushed Cheetos and Mountain Dew yet, but I did try the conventional stuff. I will see if I can get the Amsoil GL-4.
GA Architect
SILVER Star
FWIW: This GL-4 is in mine.
It is actually kind of hard finding straight 90W isnt it? I am running a 80W90. I think Yota dealers may have straight 90W. That said I am a firm believer in quality lubricants. Amsoil and Redline make some top notch stuff. I will most likely go the Synthetic route next change
I have Royal Purple 75-90 in mine. It sounds like it’s going to explode at 3k RPM, but it’s never not sounded like that and it hasn’t exploded yet. So...(shrugs)
fjl40
SILVER Star
This drove me crazy with all the different high quality fluids you can use for diffs, trans and transfer case. I bought 10 qts of Red Line, Red Line MT, then sent it all back. (Amazon of course). Then I thought what I've used the last 20 years before I had everything rebuilt. 90w GL1 mineral based gear oil. It worked 20 years for me, and know it will work another 20. Plus I do change my fluid before and after a run.
I used the Brad Penn GL-4 80w90 in mine as well, tranny, xfer, and diffs. Shifts like butter. Don't need Brad Penn necessarily, just hard to find a real GL-4. The GL-5 is fine for diffs, and maybe xfer, but not for tranny.
Castrol VMX 80
I used the Gl-4 amsoil manual transmission in BOTH the transfer case and transmission. Service manual says GL-4 in both and apparently there is a seal that can go bad between the two so I figured same oil would be fine.. GL-5 in the diffs.
WarDamnEagle
SILVER Star
Redline synthetic MT90.
rrv333
SILVER Star
I run Royal Purple and RedLine in my 40 and 62. The price for quality proven oil is a whole lot cheaper than a new/rebuilt tranny or diffs IMO.
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Is it just a drain and fill or is anything done to clean out the old and then fill. In other words.. is it necessary to remove ALL old lube before new lub goes in. If so. With what?
The ‘82 has never been done and I am getting to the point of getting it going again.
The ‘82 has never been done and I am getting to the point of getting it going again.
- Thread starter
- #15
Thanks to all of you that shared your experiences and recommendations. I am going to check out the products and get the fluid changed. Thanks for being a great resource for LC owners.
