Differential and Transfer Case Fluid Change

Hello. I'm 100% positive that this topic has been raised numerous times, I simply can't find what I'm looking for exactly. I purchased a 2019 SR5 TRD Off Road with less than 23K miles this past December and the truck has been great. Oil changes are a snap and for all the stuff I can't do my local Toyota dealership has been very nice to work with. I'm coming up on 30k and I'd to change my own differential and transfer case fluid. After reviewing the owners manual I found the correct gear oil to use however I cannot for the life of me find the exact gasket part numbers. I'm finding a lot of conflicting part numbers or when I run them through the parts store on the Toyota website it shows an incompatibility. I'd like to just clarify and confirm that I have all the correct parts for this job before I have a 7200 pound paper weight in my driveway. Being able to do routine vehicle maintenance are among the life skills thats been lost on my generation by and large.

Rear Differential Fill/Drain Plug Steel Crush Gasket: PN:12157-10010 Qty. 4
Front Differential Fill Plug Steel Crush Gasket: PN:12157-10010 Qty. 2
Front Differential Drain Plug Flat Copper Gasket: PN:90430-24003 Qty. 2
Transfer Case Fill/Drain Plug Flat Aluminum Gasket: PN90430-A0003 Qty. 4

I know they sell kits on Amazon that come with all the gaskets needed to accomplish this task but I'd prefer to spend the money on Toyota parts for this stuff. I went to the parts department at the Toyota Dealership but the guy there that day was reluctant to give me the part number without a specific part name saying he didn't want to have any liability for giving me the wrong part number. I live in Chicago and folks here seems to be scared of their own shadows nowadays. Thanks for the help.

 

this is all you need for both diffs. transfer case doesn't have any washers.

 

No gasket required for the transfer case. Just some Teflon paste or tape. Not to tight. I ordered a kit that came with the crush washers for the differentials off of Amazon. Some of them we’re not used. And I’ve heard of people being able to reuse them multiple times without issue.

 

you should have no problems removing any of the bolts because the truck is newer, but always remove the fill plugs first so you dont drain the fluid out first then find out you cant remove the fill plug. I just changed all of mine a couple of weeks ago. front diff was the hardest of the three because space is limited because you have to keep truck level so I just parked it in my garage with no jacks. transfer case is second hardest, mostly because the plugs are pipe thread and call for i think 18 ft-lbs of torque, but you feel like youre overtightening compared to how they were on there in the first place. also dont remove the transfer case skid plate because it's an absolute pain in the dick putting the set of bolts in on the front side because theres no room there to put a socket. just let the oil drain out of the hole in the plate. rear diff is easiest if you remove spare tire. plenty of space to work around back there. last thing, the crush washers have a flat and curved side to them, flat side goes against bolt head and curved goes against the diffs so it can form to the surface.

 

Outstanding! Thanks guys that's a huge help. I believe I need to drive around for a few miles in 4x4 to loosen up the gear oil to make draining a bit easier.

Most consistent and reliable torque specs I have found:

Motor Oil Plug: 30 ftlb
Rear Diff Plug: 36 ftlb
Front Diff Plug: 29 ftlb
Transfer Case Plug: 26 ftlb

Skid Plate Bolts: 21 ftlb
Skid Plate Screws: 48 inlb

 

Thanks for the tips, very helpful.

 

No problem man. Also i would suggest switching the diff fluid to the amsoil severe gear 75w-90 for the diffs. If you order it from their site and get the membership which is like $10 for a year you will save a lot of money buying a 12 at case of the oil and if you don’t get the squeeze bags pick up a pump from Amazon to pump fluid in

$17 Slippery Pete Fluid Pump for Gallon Bottles and Wide Mouth Quart Bottles (Not for Standard Quart Bottles) - Transfer Gear Oil, Transmission and Differential Fluid, Antifreeze with This 30cc Hand Pump

https://www.amazon.com/gp/product/B07DTS8N7P/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8

this is the one i got from amazon

https://www.amsoil.com/p/severe-gea...s4aPRSPdq6OzHcWOGcaAsyoEALw_wcB&code=SVGQT-CA

got the case of 12 of the regular qt bottles for $169 which is enough to do 2 services of the front and rear diff. ends up being about $14 a qt.

 

I was gonna either go with Royal Purple 75W-90 or Ravenol 75W-85 for the gear oil and the 75W for the transfer case. I'm not a mechanic by any stretch, I fight fires and fix guns so I'm taking my car from the approach of firearms and trying to get manufacturer torque specs and appropriate fluids. I know that people have a thousand different opinion about a thousand different vehicle oils so its tough to discern from the hobbyist and the professional (or experienced).

 

This truck also needs to last me at least a decade so I'm not against buying the best fluids to keep this thing running as best it can for as long as it can.

 

Same with the torque specs and appropriate fluids, but just from my personal experience since I switched to amsoil for the diffs i noticed the engagement and disengagement of the 4wd system is quicker and a lot of guys have switched to 75w-90 as its a more common and thus lest costly oil and there is really no difference between the 2 and is a completely suitable replacement for 75w-85. There's also a lot of guys that run royal purple or rav and have had a similar experience. you really can't go wrong with any of them. But for the transfer case i'd really only use the toyota oem 75w fluid.

i changed my transfer case at 30k as well and it looked damn near new to me, so if you don't use 4wd a lot or drive on really dusty roads, you can probably change that interval to 45k or so, but i know the oil is expensive for that, but i figure that since i'm already down there changing the diffs i'd rather just do them all at the same time.

 

Good to know I'll buy the Toyota OEM 75W gear Oil.

 

yeah it just sucks you have to use i think 1.5 liters for it and they only sell it in 1 liter cans, so you have to buy 2 everytime you do it. Cheapest place i found was sparks parts and used either freeship or freeshipping as a code to get free shipping. the cans it comes in suck, so i completely drained out one of the diff fluid bottles, poked a hole in lid of can with a screwdriver and dumped it into the qt bottle to make it easy to pump into transfer case.

 

Transfer Case Torque - Be Extremely Careful. The torque is listed now as 18 ft/lbs. Even this will seem crazy tight as your putting in the plugs since its an expansion fit on an aluminum case. If you go to 26 you better be careful.

 

Heres the service manual pages for diff and transfer case. will be same for your year.

 

I was just wondering about pumping it out of the can, reminds me of my how my grandfather used to have to throw a cans of oil in his old Lincoln every few fill ups at the gas station and would always end up forgetting the can under the hood and then having to run out at a stop light to take the can out and hurry to get back in the car.

I've ordered from spark parts before and they are a great source for tundra stuff I found. I'll try those shipping codes.

 

Roger that, see this is what I'm talking about getting the proper manufacturers specs, especially when it comes to torque.

 

This is awesome! Thank you.

 

Sub'd

 

no problem i got the access to the toyota service site for 2 days and downloaded everything i possibly could over those 2 days as it's like $20 for a 2 day pass.

 

That would be nice to have ;-)

 

https://drive.google.com/drive/folders/183Yn0Dc5pzPpDJL8Me-H77x17OvDx4zS

That's everything I was able to pull that was maintenance related and a few other things i figured i might need during the life of the vehicle.

 

Your'e the best!

 

That's why we have this forum, to help others out man!

 

So on a related note. Why is it that changing these doesn’t seem to be in the service guide for 3rd gen? Quite possible I missed it but only recall seeing intervals for brake fluid and long life coolant in addition to oil? Again, if I missed I apologize, it might also be this doesn’t apply to my specific year?

 

Prepare yourself for the price. It will be shocking. Also prepare yourself that if you don't spill any, you will be throwing away 1/4 of it. I just did mine at 48,000 Km (not sure what that is in America's, maybe like 30k) and it was so new looking that from now on I'll probably only do it every second time I do the diffs.

 

Big time help. Appreciate the links you have listed, I have them on my cart . I was gonna get the redline 75w-85, thats what my manual requested for the 2017. Is there any difference between that to the 75w -90. I wouldn’t mind using the Amsiol as long as its ok. Im already getting the OEM 75w for my transfer case oil.

 

if you do the method i mentioned of dumping it into one of the diff fluid bottles after draining it as much as possible ( getting a very tiny amount of diff fluid won't make a difference, I turned mine upside down for about 20 mins to get as much out as possible) you can technically save about 0.4 liters so on your 3rd transfer case fluid change, you'll only have to buy 1 liter

 

There's really no difference between the 2 oils. You will actually get slightly better wear protection using the 90 vs 85. I've done a lot of research on this as I was in the same position as you were and I landed on the amsoil being the best choice for me as I've never seen anything negative on it. It's a lot better priced than the toyota oem 75w-85 and overall I think it's a better product. I wish amsoil would make a suitable replacement for the transfer case.

https://www.oildepot.ca/can-75w-90-replace-75w-85-api-gl-5-gear-oil/

Also since you're in NV I would say the 90 is better anyway because it's better for high temp environments.

Severe Gear 75W-90 is formulated to provide elite wear protection. It is designed to withstand high horsepower, heavy loads and extreme heat or cold.

 

Once again, thank you. I will definitely join the membership then. I just went to the link and will get that.

 

yep definitely worth it for the 10 bucks. I ended up using a little more than 6 qts for both my diffs as it was my first time changing them and I was a little overly cautious about getting the right levels in them which resulted in me wasting a little more than was necessary letting it drain out, so next change I'll just have to buy 1 qt.