Rear Differential Fill bolt is stuck/seized

[ddicosmo]

Does anyone have any recommendations as to how I can get the rear differential fill bolt off my 2008 SR5v6 4x4? I have 35,000 on it and I went to do the rear differential and cannot for the life of me remove the 24mm fill bolt. The vehicle has 35,000 miles on it and the bolt looks like it is almost fused to the differential! I hit it with WD40 two days in a row but it is not coming off. I'm at the point where I'm starting to strip the bolt and backed off until I can figure something out here. I don't want to use a torch or anything like that since it is close to the gas tank. Does anyone have any suggestions? Has this happened to anyone else? Finally, I'm using Mobil 1 75w-90 gear oil for the front, rear diffs and the transfer case. Is this good oil? Thanks,

- Dave.

 

[sonerick]

I know you said you don't want to, but heat is probably your best bet.

Alternatively, you could try a cheater bar (pipe slid over the end of your wrench to give more leverage), PB blaster (a little bit better than wd-40), hitting it with a hammer to break it free, or tightening before loosening to break it free.

If you use a cheater bar, have someone else hold the socket tightly over the bolt while you apply pressure to the end of the bar, especially if it is starting to strip (which it shouldn't be if you're using the correct size socket). With enough leverage, you can loosen just about any bolt.

Edit: I also used M1 75w-90 in all 3 units. No problems, good stuff.

 

[CookieRoe]

Does anyone have any recommendations as to how I can get the rear differential fill bolt off my 2008 SR5v6 4x4? I have 35,000 on it and I went to do the rear differential and cannot for the life of me remove the 24mm fill bolt. The vehicle has 35,000 miles on it and the bolt looks like it is almost fused to the differential! I hit it with WD40 two days in a row but it is not coming off. I'm at the point where I'm starting to strip the bolt and backed off until I can figure something out here. I don't want to use a torch or anything like that since it is close to the gas tank. Does anyone have any suggestions? Has this happened to anyone else? Finally, I'm using Mobil 1 75w-90 gear oil for the front, rear diffs and the transfer case. Is this good oil? Thanks,

- Dave.

First problem is the use of WD40, you need to use "blaster" on it. Spray, let sit for a day, come back, get a screw driver on the bolt and give it a good WACK. Should knock it loose. That is what I did. Worked like a charm. Before I was practically hanging on it.

You are using the same gear oil I use, you are good to go!

 

[DC runner]

Yep. I have had issues with every diff bolt in every Toyota I have ever owned. Usually I take a propane mini torch and a huge A** breaker bar and it will eventually come off.

This last time, I didn't have the time and let the dealership do it.

But, don't worry. It appears to be a Toyota common occurrence. Welcome to the "I can't get my Diff Bolt out" club.

 

[KidVermicious]

WD40 is not a very good penetrant, it's a better water displacer. Liquid Wrench or PB Blaster are good off the shelf. I'm told that 50/50 ATF and acetone will free anything, but I've never had a stuck so bad that I needed to try it.

Soak it in PB Blast for several hours, heat the bolt real good, and then pound an SAE socket a 1/2size too small over the thing and get your cheater bar on it. Plan on replacing that bolt.

 

[ddicosmo]

Thanks everyone for the responses. Does anyone know the part number for the rear diff fill bolt for the 2008 4x4? I will probably need to replace it.

 

[d_clark]

Rear bolt : 9034118006
gasket : 1215710010

REAR AXLE HOUSING & DIFFERENTIAL. Fits: 2008 TOYOTA 4Runner 4000CC 24-VALVE DOHC EFI, AUTOMATIC 5-SPEED | Village Toyota Parts

 

[nevada]

use a 6 point socket, and give it hell!

also make sure you're turning it the CORRECT way.

i know, EVERYONE knows, but, you would be surprised how often it happens...

 

[Antman]

soak it in pb blast for several hours, heat the bolt real good, and then pound an sae socket a 1/2size too small over the thing and get your cheater bar on it. Plan on replacing that bolt.

^^^^^^^this, make sure it's a 6-point socket .

 

[mrrab]

Just wait til you get to the front diff. drain bolt. That's an hex socket and I guarantee you will strip it. That was my problem bolt. Had to take it to the dealership.

 

[nevada]

Just wait til you get to the front diff. drain bolt. That's an hex socket and I guarantee you will strip it. That was my problem bolt. Had to take it to the dealership.

for internal hex bolts, ALWAYS smack them with a hammer before you ever try removing them.

get a punch, or socket with extension, and tap as STRAIGHT into the plug as you can. this will shock the threads, and should make it MUCH easier to remove.

 

[Zuke]

2 good days of soaking it in pb blaster then a 6 point 15/16 socket (undersized 22mm) and 24"+ breaker bar. Mine had 150k miles on it and a decent amount of surface rust. A long breaker bar will make you into a HULK.

 

[ddicosmo]

So I managed to borrow a breaker bar from a friend and have soaked the bolts in PB overnight. I'm going to attempt this again today. The only thing I don't have is a 6 point 24mm and 15/16 socket. THe ones I have are craftsman good quality but they are not the 6 point ones (they have more than 6 points). I went to Sears to buy a 6 point socket but they were all the multipoint ones. I'll give it a try and see. Thanks for the responses and I'm NOT looking forward to those front hex bolts! (I'm starting from the back and working my way to the front).

 

[jimmied]

I need to do mine soon and this thread makes me nervous. Lol.

While we are on topic. What size sockets/ hex tools do we need for all three services?

 

[jow]

The Trick is the 6-point socket, 18” break over bar and good slow square pressure on the soft shallow bolt ‘s head or it will round very easy. With the spare removed, giving you plenty working room. If it rounds, my guess would be to file 2 opposite sides flat and try vise grips. Why get to the harder options if you can avoid the matter? Hopefully the replacement bolt’s heads are harder and thicker.

 

[Atlanta_man]

Makes me appreciate my Acura RL where I just recently worked 7 of these loose. Transmission,2 on the transfer case, and four in the sh-awd diff.
They have a square recessed indentation that fits a 3/8 inch socket drive. Even so my 3/8" x 20" breaker bar was essential.

Why so tight ?

 

[ddicosmo]

I was easily able to get both the fill and drain bolts off no problem. The key was hitting both bolts with WD40 and PB for two days and then using 24" breaker bar and a 15/16 6 sided socket. This worked perfect. The breaker bar is KEY!! Thanks everyone for the help. Now onto the front diff and transfer case!

 

[KidVermicious]

Don't forget the anti-seize when you replace them.

 

[JoshKY]

Happened to me as well and stripped it out by not using a 6 point wrench. Found out on another forum this plug has not changed from gen to gen, the dealership typically carries them in stock.

 

[CXS]

Point to be emphasized here is that everyone should always remove the fill plug before the drain plug. It really sucks to drain a diff only to find you can't fill it back up. I learned this the hard way on my old Land Cruiser. :ybrick: