Topic: Gear oils being used

[019854Runner]

Just to be sure, so the F/R Diffs, transmission, Marlin Doubler all uses 80W/90 Gear oil? 1985 4runner with Marlin Doubler.

[redneckcustoms13]

Yes.

[SqWADoosh]

MT-90 in the trans and cases.

[blackdiamond]

MT-90 in the trans and cases.

Is better but not required. I know why for the transmission with GL-4 and syncros, but why is it superior in the t-case?

[SqWADoosh]

Is better but not required. I know why for the transmission with GL-4 and syncros, but why is it superior in the t-case?

I run same in both in case of seal failure causing migration and for ease of using the same. My cases always ran great and quiet using it.

[blackdiamond]

I run same in both in case of seal failure causing migration and for ease of using the same. My cases always ran great and quiet using it.

That makes sense. I have never spent the money for Redline anywhere but the transmission and even topped that off with the Valvoline blend I used everywhere else.

[Gnarly4X]

Mobile 1 is just as good and less expensive.

[blackdiamond]

Mobile 1 is just as good and less expensive.

For lubrication purposes, yes, but Redline is GL-4 instead of GL-5 (that is GL-4 compatible) and works much better with the transmission syncros. You can feel the difference.

[OVRAROK]

I run mt90 in trans, 80/90 in cases and diffs, I drain and put new in every 2 years. I'm running MC eco seal at trans output.

[Gnarly4X]

For lubrication purposes, yes, but Redline is GL-4 instead of GL-5 (that is GL-4 compatible) and works much better with the transmission syncros. You can feel the difference.

As I remember, when I spoke to a Redline tech rep, they recommended MTL for my W56 transmission.  It made a very noticeable difference in shifting.

This time I tried Mobil 1 75W-90 Synthetic.  I noticed a much smoother shift and quick gear mesh than the non-synthetic I had in before.  I can't effectively compare the two (MTL vs Mobil 1).  Since my high ambient temperatures here in AZ can get up to 100+ degrees for 3 to 4 months, I decided to try the Mobil 1 75W-90.  For a W56 transmission, my 1986 Toyota Repair Manual says:  Oil Grade:  API GL-4 or GL-5, Viscosity: SAE 75-90 or 80W-90.

I would bet that Mobil Oil is aware of any issues with "yellow metal" and synchro gear corrosion, and have formulated their gear oil to meet the required synchro lock up on the shaft during shifts.  The brand of synchros is probably more important for proper synchronizing than the gear oil.  My transmission shop here said they only install Toyota factory synchros in these transmissions because the alloy is the best for proper synchronization.

I believe I could not tell the difference between Redline and Mobil 1 in my transmission as far as shifting.

Redline is an excellent choice, but at the time I was adding gear lube, it was way more difficult to source.  Difference in price for 7 quarts was about $50, so Mobil 1 was a little more economical and budget friendly at the time.

Gnarls.

[:)bestgen4runner]

As I remember, when I spoke to a Redline tech rep, they recommended MTL for my W56 transmission.  It made a very noticeable difference in shifting.

I 100% concur

[H8PVMNT]

I tried the sta-lube GL 4 and it shifted better than the GL 5 too.

[T-Revv]

Redline is great product.  We use MT-90 in the transmissions and Tcases here at Marlin.   Redline also makes this super cool product called shockproof, which is a multi viscosity.  Shockproof is cool for the diffs, but I think its a little too sticky and gums up transmissions and tcases.  Mobil one I know makes some good products too, but im just not familiar with them, and haven't ran them personally.   

[:)bestgen4runner]

Redline is great product.  We use MT-90 in the transmissions and Tcases here at Marlin.   Redline also makes this super cool product called shockproof, which is a multi viscosity.  Shockproof is cool for the diffs, but I think its a little too sticky and gums up transmissions and tcases.  Mobil one I know makes some good products too, but im just not familiar with them, and haven't ran them personally.

I use Shockproof in the front and rear diff. Best diff oil money can buy.

[mudmaster]

I use Shockproof in the front and rear diff. Best diff oil money can buy.

Heavy or lightweight?

[:)bestgen4runner]

Heavy or lightweight?

I have always used the Pink/Red heavy stuff. It's $$$$$$ but Hard to beat it.
I like other people strain it when I drain it, then put it right back in and top off with new.


From RedLine
•Film thickness greater than an SAE 75W250, yet low fluid friction like 75W90
•Many performance racing applications like Sprint/Midget/Dirt Late Model Differentials, Detroit Lockers and spools, NHRA Top Fuel and Funny Car rear ends
•Not recommended for most synchro applications due to the product's extreme slipperiness

[blackdiamond]

I have always used the Pink/Red heavy stuff. It's $$$$$$ but Hard to beat it.
I like other people strain it when I drain it, then put it right back in and top off with new.


From RedLine
•Film thickness greater than an SAE 75W250, yet low fluid friction like 75W90
•Many performance racing applications like Sprint/Midget/Dirt Late Model Differentials, Detroit Lockers and spools, NHRA Top Fuel and Funny Car rear ends
•Not recommended for most synchro applications due to the product's extreme slipperiness

What do you notice in the diver seat?  You can feel a transmission feeling better, but can you honestly tell any difference with the diffs?  I ask because I doubt that our actual use would reduce the lifespan of a diff using conventional. I run blend I think.