Off-Road Tires & Lift cause Rear Diff. Damage?

Damn we’re good

 

If we replace the whole rear assembly though, we can use a non locking, right? Thanks.

 

You’d need to replace the entire axle. The axle housing is specific for the locking diff models. It’s meant to accept the factory locking diff.

 

yes, he has the 8.0 locking rear axle. you would want the 8.4 non locking axle. that's going to be more expensive than just replacing the third member in the locking axle

 

Thanks. I know his has a sticker on it that reads C9. Not sure what it represents but know a non locking has a C3 sticker. Who would you buy from? Thank you.

 

Great minds and all

 

a junk yard would be my first place to look. but then you have deal with an unknown axle

 

Update:

After considering all the good advice from folks here, I decided to repair the truck instead of cutting our losses and running. The mechanic pulled the rear differential off yesterday and it is destroyed. The axles are 100% fine. So, I have purchased a new rear differential directly from Toyota at my mechanic’s cost. I know you’re all cringing at the thought of me having bought from Toyota but, we are not car people. I can rest assured that this will be a reliable rear diff. that should never go out again. Once I learned that the axles were fine and that I only had to replace the RD, I was willing to pay the price for new. Having lost my 23 year old sister in an auto accident years ago, safety is very important to me. The most important factor, actually.

I picked the destroyed RD up from the mechanic and took it to Toyota to purchase the new one. I asked for one of their mechanics to look at it before Ipaid them $2,000 for the new one. They obliged. He was very willing to look at it. He rubbed his finger on it, smelled it and said it wasn’t the correct oil. Add to that that my mechanic mentioned that when he drained the oil it “came out like water” and “ it should have been thicker”. I believe when it was replaced the last time, they most likely used the wrong oil. Ugh. Ridiculous.

Thanks again to all of you for all the guidance. It helped me make areasonably well educated decision on how to proceed. I really appreciate your time and that you shared your expertise with me.

*I wanted to upload a couple of videos here from my IPhone but, it won’tletme. Here are a couple of pictures.

 

Geez. The wrong oil? Every time I feel like I'm bad at my job, I'm going to think about that.

That said, I might be a little concerned about bearings in the axle. They're designed with the same oil specs as the RD.

 

Well, I can’t really prove it but two seperate mechanics feel it was incorrect oil one of which was a Toyota mechanic.

Thanks for the heads up on the axle bearings. I’ll mention it to my mechanic. He’s working on it right now.

 

Good lord that expensive. Like water- Maybe he went through a deep puddle and sucked water Into the diff through the breather ? It’s common for people to extent the breather out of harms way on these trucks. Very cheap mod If he offroads through water or creek crossings.

 

The rear axle bearings are sealed and not lubricated by the gear oil.

 

Oh no kidding? I'll be quiet now.

 

Even when hot the correct axle (

$29 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90) oil would drain like molasses. Even if the shop used 85W-140 it's still a thick and sticky feeling oil. Now I wonder what kind of oil would cause this damage because even if water got in the system, that can easily be determined when opened/drained as it would look like watery mud.

 

Oh, some good news! Thank you!!

 

Thank you. I don’t know the answers. The car was cold and had to be pushed into the mechanics bay. I know he said it was very dark/burned and poured out like water. I’m not looking to throw blame. My son did drive it on pavement with the lock on. That could be the cause. The Toyota mechanic who looked at it yesterday in the back of my car said if it’s not the proper oil it will create too much friction and get too hot. That’s all I can share with you. Thanks.

 

I appreciate your thoughts anyway. Now, you’ve learned something new so, it’s all good.

 

Since you seem to be in great communication with your mechanic, you should ask him, "just out of curiousity, how do you get all the metal junk out of the housing?" He should say something like, "I pull the axle seals out, blow with an air blower, spray with brake clean, blow more air, spray more brake clean, pull a rag through the tubes, spray more brake clean, pull another rag through. When it's clean enough to eat off of, then I start assembly."

 

If it was dark then there was no water intrusion. Once you get it fixed, just simply unplug the rear locker behind the switch or specifically just tell your son not to use it again unless to get out of being stuck. Hopefully he learned his lesson this time around.