HELP: Rear Axle issues

9/16/16 update:

So I replaced the rear axle seal....the original wasn't bad. There was no groove where the seal was rubbing....everything looked perfect. However, it's still leaking. My father-in-law said it may bent a bent axle (the actual axle inside the housing). He said this may be causing an oblong rotation, which may cause the seal to have gaps in it when spinning. This may also explain a little bump I feel at around 45-55 mph.

Thoughts?

UPDATE:

When I bought my '03 4wd last year, I knew it had some rear end issues. After my last tire rotation, I found out it was a busted axle seal on the rear driver's side. Ordered 2 axle seals for like $20 a few months ago and plan on installing them this weekend.

What is throwing me off is I saw the guy I bought the truck from last week and told him what the issue was and he said he had replaced axle seals a few times and they always bust. He said he had the whole axle rebuilt and tried other things, but the seals kept blowing (whether this is true or not, I dunno).

The only thing I can think of is that pressure us building up and the gear oil is looking for the path of least resistance to escape: the axle seal. If this is true, I'm thinking the diff breather may be clogged. I have all the parts to do a breather extension I ordered a few months ago, so my plan is to do that, put in the new seal, and change my gear oil.

Thoughts?

Original post:

Hey guys,

I bought my '03 TRD 4x4 almost a year ago and the guy I bought it from said he'd been having some rear end issues, but could never really figure out what it was. After inspection, I noticed he had 2" metal blocks to lift the rear, so I assumed it was either axle wrap or the blocks rubbing against the leaf making noise when braking.

My father-in-law said he thought the diff fluid was low, but I don't think that's it (although, I'm checking and changing it this weekend, anyway).

Here's what's going on: whenever I brake, you can hear like a metal grinding, twisting type noise. It only happens on a rotation, much like when your disk brakes get a spot in them. To be clearer, if I'm slowly braking, I'll only hear the noise in one spot of the rotation. It's not a constant noise when I break, only in like 1/8th of the rotation. From inside the cab, it sounds like it's coming from the back right, but it could be the left side.

Also, I don't know if it's related, but sometimes when I brake, the truck shakes really bad. I've never owned a Taco with ABS, so I thought it may be that, but now I'm thinking it may be related to my rear brake/axle issue.

I'm going to try to take a video of it from underneath the cab, but I'm still working on how to do that without duct taping my phone under my truck lol.

I've got access to almost any tool I need, so I'm hoping this is something I can diagnose and fix myself. Any help would be greatly appreciated.

Thanks

 

Have you checked the rear brake shoes?

 

I have not. I really don't know much about drum brakes at all, so I really wouldn't know what to look for. I'm going to look for a DIY now. My father-in-law is pretty automotivally inclined, so I won't be diving in completely blind.

 

Yes sounds like maybe a shoe rub issue might be the diff but also could be a wheel bearing or brake issue

 

Okay, so I'm going to start with the brakes then. I found a YouTube video and a somewhat helpful step-by-step (minus pics) on here, so hopefully it won't be too disastrous. Thanks!

 

Beano before quiet after.

 

Okay, so Saturday I'm going to be jacking my truck up on my uncle's lift and replacing the seal in the rear axle and then changing out the rear diff. oil. My father-in-law thinks it's leaking gear oil due to the bad seal, so maybe the oil is causing the brake to act up. From everything I've read, rear drum brakes don't really wear like disk brakes do, so I just don't think it's that. We'll see

 

With those rear lift blocks, the u-bolts can loosen up. I would check the torque of all 8.
You don't really need a torque wrench, just make sure they are all good and tight.

 

I'll do that while I have it lifted. Thanks. I plan on replacing them with AALs eventually

 

I'd check wheel bearings and at least open up the drums to make sure nothing looks terribly wrong.

 

I'll add that to the list, too! Thanks.

 

UPDATE: I got my tires balanced and rotated yesterday and the inside of my left-rear tire was covered in rear end dope. Upon further inspection, we determined that it was in fact the rear axle seal. Luckily, the rear end dope was not low, so there was no risk of burning anything up.

My next question is this: from everything I've read, this is a really easy job to do, but I have read some conflicting information regarding inner and outer seals.

Do the first gens just have 1 seal? From what I've gathered, the first gens only have one seal.

 

UPDATE:

When I bought my '03 4wd last year, I knew it had some rear end issues. After my last tire rotation, I found out it was a busted axle seal on the rear driver's side. Ordered 2 axle seals for like $20 a few months ago and plan on installing them this weekend.

What is throwing me off is I saw the guy I bought the truck from last week and told him what the issue was and he said he had replaced axle seals a few times and they always bust. He said he had the whole axle rebuilt and tried other things, but the seals kept blowing (whether this is true or not, I dunno).

The only thing I can think of is that pressure us building up and the gear oil is looking for the path of least resistance to escape: the axle seal. If this is true, I'm thinking the diff breather may be clogged. I have all the parts to do a breather extension I ordered a few months ago, so my plan is to do that, put in the new seal, and change my gear oil.

Thoughts?

Also mods, could you change the title of this to 'Need Help From Folks w/ Rear Axle Knowledge!' @sean266 @tcBob @ForeRunner

Thanks in advance, everyone.

 

Oh

 

bump

 

Do you have a temp gun ? You could point the red dot at the rear diff after you have driven the truck .
Normal operating temp is approx 120 degrees .
When you remove your axle seals , check the axles for grooves where the seals ride on the axle shaft . Its common for the axle seal to cut into the axle . Once the groove is made in the axle , it will not seal even with a new axle seal .
Its a great idea to make sure the vent line is clear or the diff fluid will heat up and find the path of least resistance .