75w140 in transfer case and rear diff?

Looking for some expert advice. Part of some recent work a shop put in Lucas 75w140 in both rear diff and in transfer case. Not fixing anything related to transfer case or rear diff, just servicing.

Stupid me did not look at the spec on the bill until 3 weeks later. I just assumed they would go 75w in transfer case and 75w85 in rear diff.

2016 TRD Off Road, automatic, 45,000 miles.

10,000 miles off road driving in last 3 summers.

Kelowna BC, normal temps from Spring to Fall range from 50F to 95F.

Winter temps usually in the 13-40F range.

Not towing, but about 35 offroad trips spring to Fall, usually 500 - 600 pounds of gear in the truck.

Thoughts? Should I go back and have them replace the oils under my driving conditions or leave it? More concerned about the 75w140 in transfer case, I doubt much issue with it in the rear diff.

 

Toyota provided lubricant specifications as determined by engineers for a reason, neither product meets those specifications.

You paid a shop to service your truck, the responsibility is on them to use the correct lubricants. They did not, nor did they consult with you about substitutions.

 

The manual is pretty clear on this matter. I would refer to it when discussing that with the shop.

 

They can swap the fluids now or pay for the damages later.

 

Yeah it is looking like that is the case. Never seen that before where different spec oils are added, and without consultation. It is unfortunate, they came recommended and talking to the owner and mechanic they seem pretty knowledgeable and many years in the biz. They were pretty fluent talking about differentials. Toyota not their specialty, but their mechanic is a longtime and current Toyota 4x4 owner and talking to him he knew a lot more than the dealers when it comes to hands on knowledge and troubleshooting.

So not sure why these oils without discussion. I just happened to have a Tuesday appointment so will have to get the ball rolling at that time.

I am not fond of dealers and was looking for a solid mechanic to depend on. My back and neck preventme from doing the typical service work under the truck. It sucks after a lifetime of DIY.

My 4th 4x4 in last 35 years, but first Toyota, and I find I usually have to do all the troubleshooting when talking to dealers. Diagnosing not a dealer specialty.

 

I’ve been running 75/140 in the diffs for 10 years, now. Aint blowd up, yet. about to turn 159k

 

Generally speaking it should not be an issue. I wonder though if the 3rd gen have different requirements for diff than 1st and 2nd gen?

The 75w140 in the transfer case is a bigger question.

 

75/140 in my TC. Send it. You’re fine

 

synthetic? 75w140 synthetic added to my 2016 in rear diff and transfer case.

Problem with internet is there are a hundred different answers...

 

"...The internet has a hundred different answers..." -- Toyota engineers provided one also. I trust the engineers more than the internet.

 

Yes

 

It's the cold weather performance that would bother me with that spec. If you lived in FL or the Southwest, I don't see an issue with it. With the cold weather you experience, I would definitely get it changed.

 

Again, Toyota changed the fluid recommendation from the 2nd gen to the 3rd gen for the TC. The people saying it's fine don't have the same generation as your truck.

The problem is the shop went off menu without discussing it with you beforehand. Might as well just put 10W40 in there since that's good enough according to the internet.

It's not hard to follow the manual. The shop simply used what they had laying around to save themselves some money, has nothing to do with your trouble.

 

Yup, that is my guess too. Some shops will just use what they have on hand. I am not concerned about one maintenance cycle though. Oil change is due soon, will buy the oils myself before then, they can drain and add them. None of those oils will cause any issue over a month. Temps are in the 60F to 85F range now so nothing drastic and I will get it all done at same time.

 

75/140 in my diffs (regeared to 4.56). Keep 75-90 in the T-case.

For heavy use, offroad use esp., you want the thicker oil in the diffs. And DINO lube, not synthetic. This is why: https://eastcoastgearsupply.com/files/PDF Files/ecgs-gear-oil-recommendation1.pdf

 

And one correct answer, whatever Toyota states to use.

 

They stated Amsoil/Redline Synthetic is better.

 

You know how I know you didn't read it fully?

 

You don't, because I read the whole thing.

And this part as well,

Amsoil severe duty: Better than all economy Dino's and all synthetics on the market, but marginal over a quality dino with additive package

 

75W140 is not recommended in the tcase, you can drain and fill it yourself with 75W80 GL4 ie Redline MTL-LV ($20) and a few others including OEM ($70), Ravenol, etc.