If you don't want to read my ramblings, skip to the bottom

WOW what a difference, especially in the transmission. I replaced the following:

Rear Diff with:
DuraBlendŽ Synthetic Blend Gear Oil 80W90




Front Diff and transfer case with:

Mobil 1 Synthetic Gear Lube LS 75W-90


Trans with:

Valvoline Maxlife Dex/Merc (WITHOUT THE STOPLEAK!!!!!!, stopleak version = bad)



The truck just turned over 109k miles and has had every service record performed at the dealer which I have in writing that came with it when I bought it.

The transmission shifts super smooth now and feels amazing. It wasn't bad before, but there is a definite improvement. The old fluid was a dark red color and didn't look too bad, but was due for a change. It appears the dealer had only done drain and fills 4-5 quarts at the trans fluid change intervals. When I did it, I used 18 quarts to make sure all of the old stuff was flushed out and the fluid was bright red coming out. I did the "disconnect the trans cooler line, start engine and flush out 2 quarts at a time method" and it worked great.

The rear diff fluid was black and looked like it was still the original fluid. Looking at my paperwork it looks like the dealer never changed out the rear diff fluid. I went with a synthetic blend for the rear due to not being able to find a 100% synthetic in 80W90 at a few local stores and it should serve its purpose very well. I believe AMSoil makes synthetic in this weight and I may eventually switch it out, but this is a good stepping stone to get all of the old original oil out first.

The front diff fluid looked brand new when I drained it, strange how only that was replaced.

The transfer case was also black, although it never gave me any issues when I used it.

Summary
Replace all your fluids!!!!!! IT WAS VERY EASY and took me all of 2 hours taking my time. I'm glad I did all of mine, because I thought all the fluids were new(er) in my truck and I was wrong. This was very easy to do and cost me around $120 including all the gaskets I ordered from the dealer. Yes, even with the high mileage I did go with synthetic transfer case and front diff fluid and so far nothing is leaking or acting strange. I will eventually switch the rear diff to 100% synthetic once the synthetic blend is in there for a while to get all the old original stuff out.

Already did power steering and coolant, so next up will be a brake fluid bleed and I'm done for a while.

Hopefully I motivated you to do this and you will get a lot more life out of your truck. Here is the writeup on how to do it, now go do it!!!

http://www.4runners.org/writeups/difftsf/index.html

 

good fresh lube=smooth operation.

good for any occasion

props to bud for keeping up on it. most guys forget about the diffs and what not. and are lucky to change the tranny fluid out. or even a drain and fill for an auto.

 

You got a writeup for doing the trans flush? I will be doing this soon. Got any tips/tricks? I am on the fence about doing it myself over bringing to a shop.

 

Baja,

Love the new green 4 runner. Good to have ya back. I loved reading your posts while I was a lurker years ago.

Here is a DYI tranny write-up by fellow member skjos. I do not think you will find a better one out there. The only things I did different was I broke the seal from the back right of the tranny pan, not the front. I also did not do the full flush right away but waited a couple of days. To each his own.

https://www.yotatech.com/forums/f2/h...review-166554/

 

thanks for the links and writeup


is there an advantage to flushing in a heated garage as opposed to a 50 degree driveway? Does it really matter?

 

Hey J2F42C, Thanks for the kind words! I am stoked to have a 3rd Gen back!

Thanks for the tranny DYI link. Just what I was looking for! I will probably save a few $$ and do it myself.

 

When it gets colder, it's hard to pump or pour the gear oil.

 

I thought the manual transmission only takes 2.3 quarts...? you used 18????
please help me as i just bought oil to do this and now i am very confused.... I was looking at 4runners.org (the same link you posted) as a guide and it seemed really easy

 

well for one he's automatic.


and two, he said he cleaned all of the old fluid out with that 18qts.


you don't wanna mix good tranny fluid with bad tranny fluid...so he made sure all of the bad fluid was drained out and had good fluid coming out when he drained...which equates to better operation!

 

I just ordered 3 quarts of redline and should get it soon. what would you suggest i do? maybe drain it and pour cheap oil in and drive for a week then the good pour the good oil in? or should i try to flush it? can you flush the manual trans as described above?

 

Proactive routine maintenance.

:wabbit2:

 

I have an automatic trans. The writeup says to use 16 quarts to flush the old stuff out with, but mine didn't start coming out coming out clean until 18 quarts was ran through it.

For a manual trans, all you do is a drain and fill, like changing the oil. There is no "flushing" needed. I'm not sure of the capacity of the manual trans.

 

I'm curious why you put didnt types/weights in the front and rear diffs.

 

I went with the weights that Toyota recommends. For whatever reason they want an 80W90 in the rear diff only, and 75W90 in the front diff/transfer case. I could not find a 100% synthetic locally in 80W90, so I went with the best stuff I could find locally which was a synthetic blend. It looked like the fluid that was drained out of the rear diff was the original fluid for 109k miles, so I'm going to run the synthetic blend for a little while. The rear axle seals are notorious for leaking on these trucks, so I feel a little better not switching the rear over to a 100% synthetic right now due to the myth of synthetics causing leaks. I may eventually replace it with AMSoil, which makes a 100% synthetic gear lube. We will see, either way what I put in there looks a lot better than what came out.

 

I know this is an old thread, but can anyone tell me how much 80w90 fluid for the rear axle? My rear axle is leaking and I want to have everything I need before attempting repair.

 

i believe the rule of thumb (and what i've done in the past) is fill until it starts leaking out the fill hole. I remember referencing how much I had filled to the manual and it was very close. Don't have the numbers off hand- I think it's around 4 quarts?

 

Rear differential oil (4WD, w/o Diff. lock)
2.45 liters (2.59 US qts, 2.16 lmp.qts)
Hypoid gear oil API GL-5 Above -18 °C (0 °F):
SAE 90 Below -18 °C (0 °F): SAE 80W - 90 or 80W

Rear differential oil (4WD, w/ Diff. lock)
2.75 liters (2.91 US qts, 2.42 lmp.qts)
Hypoid gear oil API GL-5 Above -18 °C (0 °F): SAE 90 Below -18 °C (0 °F): SAE 80W - 90 or 80W

Looked it up- for me it was 2.5 quarts w/o the locker.

 

Thanks, I appreciate it.

 

Remember to remove the fill plug first then the drain plug on the diffs. Nothing worse than removing the drain plug and all the fluid then not be able to remove the fill plug

 

Just wanted to bump this old thread because I found it while I was searching for something. I've only put around 12k miles on the 4runner since I did this and have had no issues or leaks switching over to the synthetic gear lube at my mileage (knock on wood).