Driveline Fluid Recommendations

I have dug through the information on here and seem to find mixed opinions, but that is expected. I am coming close to the 30k mark and want to change out diff's and transfer case fluid.

Mobil 1 75-90 seems to be the choice for F+R Diff's.

The transfer case I am not finding much information except buy the transfer case fluid from Toyota. If that's all that is available then I guess it is what it is, but not spending $150 for 2 liters of fluid would be awesome.

 

Use the same fluid as the diffs. Toyota dealers use bulk 7590 for all 3 during services.

 

Royal Purples Synchromax for transfer case. It is listed as a direct replacement for Toyotas LF fluid. And is much cheaper than Toyota’s fluid.
I did some stupidly extensive research on this. From my understanding the transfer case uses some soft metals (brass, copper) in the transfer case that are not used in the differentials. So supposedly using regular gear oil with higher phosphate levels will damage the soft metal bushings over time.
That all being said, Agent_Outside is also correct in that most dealership just put in bulk gear oil to top it off. Not sure if they would do that in a complete remove and replacement of the fluids.
I use the Synchromax because I plan on keeping my 4Runner for 6-10 years and didn’t want to take the chance of screwing something up, it’s not that expensive, Royal Purple has a good reputation when it comes to fluids and they warranty if anything happens and is directly related to the use of their fluids they pay for the repair. I used it in my Tacoma for years and never had an issue.
Personally I wouldn’t use bulk gear oil in the transfer case, and my experience with some Toyota techs and parts people is they are clueless.
http://www.royalpurple.com/wp-conte...le_Transmission_Lubricant_Cross_Reference.pdf

http://www.royalpurple.com/product/synchromax-manual-transmission-fluid/

 

Brand does not matter with fluids, oil, diff etc. Don't buy into the marketing, get the proper viscosity that's on sale. I keep my vehicles for a long time, my Tacoma currently has 200k miles on it.

 

I put Redline 75w85 in my diffs and t-case.

 

Except for the air and cabin filters; I always use Toyota OEM fluids and their dealer service. I, like the above fellow, keep my vehicles for their life span (200k). They sold it, they warranty it, so no doubt where the liability lies. No problem with either the 4Runner or Highlander.

 

I’ll be using synchro max

 

Understand lots of people buy into the hype and fancy commercials the ad agencies have plastered all over the television. You have the right idea, keep your fluids changed with the correct viscosity, period. No need to buy into all the hype... I've hit 200-K with my last two vehicles changing things by whom-ever using what-ever they use.

 

this is the proper fluid in transfer case . the diff's no problem using mobil 75-90wt synthetic gear oil has open diff so no problem.. many dealerships use this gear oil in the diff's bulk containers.
read the additives in this Toyota transfer case fluid .. this trans case has electrical parts and other metals to protect from wear.

 

just buy one qt of toyota transfer case oil then top it off with mobil synthetic 75-90wt.. ..
if you check the T case fluid and it looks good no need to change it at 30K. if you use 4wd then 30-40K is the proper change.

 

Okay, so I used Mobil 1 front and rear and the royal purple on transfer case.


Recommendations on the driveshaft lube?
Not seeing much on this, but I’m having issues searching from my phone.

 

I use mobile 1 synthetic grease. It meets the Toyota requirements. Usually can get it for $10. As long as you hit the zirks regular and after driving dusty roads.

 

My dealer uses some weird weight for the diffs in all they Toyota’s they service. I just had a big talk with them and Toyota corporate and it’s approved.

 

I don't understand why the manual even has specs, when the vast majority of people (dealership included) just put in whatever they feel like.

I would like to really know if the recommended weights are based on optimal fuel economy, wear, or both. I would gladly trade .01 MPG for better protection. On the other hand, I wouldn't want to use overly thick oil if it will eventually harm the differential or transfer case.

I'll be changing these fluids in a few months. At this point, i plan on using Ravenol for everything. They have the proper weights, and are available on Amazon. The description also specifically refers to the part number for the OEM fluid. I figure this is the safest bet.

I would love to hear some input from someone with 300-400K who has done their own maintenance. I intend on keeping this truck for a long time, and I don't want to be rebuilding differentials because I followed, or didn't follow the manual.

 

Get GL-5 spec fluid, the end.

 

Toyota doesn't spec GL-5 for the transfer case. They spec Toyota LF 75W or equivalent.

 

people use 75-140wt gear oil in texas and arizona .. high temps in those areas is why they use that 140wt.
in my area not good when the air temps drop to below 30F... some on other trucks in those areas have diff covers with cooling dissipation ..

 

toyota manual says grease the U joints with lithium based grease.. the slip yokes you use moly grease.
moly grease you just give it 2 pumps that is it. I do it every oil change.

The U joints you have to pump it until the grease flows out.. then you wipe off that old grease.. pump slow easy so the grease flows properly ..

 

Amsoil is the best replacement of Toyota differential gear oil. I get the soft pack quarts that make the job very easy with no mess.