rear axel seal done but now truck shakes

[Kinnick]

So my local mechanic who I trust and has worked on my 4runner for the last 8 years, just finished the rear axle seal job on my 1997 SR5 4x4 with 160,000 miles. I made him aware of this common problem and even showed him the thread from bigfishallday highlighting what might be some reasons for the failure. The parts he used all appear correct per the thread. I took my 4runner for a drive after the job and at first it drove perfect. Then after being on the highway for about a mile I noticed a rattle coming from the back tailgate. At first I thought maybe it wasn't shut tight but then my 4runner started to shake more in the rear end and could be felt in the whole vehicle. I decided to pull over. When I would apply the brakes the shake would actually become much less, but when I let off the brakes as I was slowing down it would shake again. I came to a comlete stop then headed back to town. As I picked up speed it drove fine for the first half mile but then it started to shake again and pretty bad when I got back to the repair shop. Unfortunatley they had just closed so I left it there to address it in the morning. Any ideas what may be causing this or what may have gone wrong during the repair job. Thanks for the help.

 

[PitbullRescuer]

Bent axle shaft.

 

[nissanh]

Did you bet the bearings done?

 

[Kinnick]

Did you bet the bearings done?

Yes, the bearings were done.

 

[BigFishAllDay]

The fact that the shaking was not present immediately, and that it seems to be affected by the application of the brakes, indicates to me that it would be an issue w/the brake shoes and/or drum.

I thought through what could be causing it, and my guess would be that the rear brake shoes are adjusted too tightly to the drum on one side or the other. As you began to drive it felt fine, but I suspect that as you kept going part of the shoe was contacting the drum, quickly heating it up and causing the shoe/drum to bind @ a single point. When you applied the brakes the shoes made full contact with the drum and the shaking subsided.

That's my take. I'd back off the adjustment on the rear brakes and re-adjust.

 

[Kinnick]

The fact that the shaking was not present immediately, and that it seems to be affected by the application of the brakes, indicates to me that it would be an issue w/the brake shoes and/or drum.

I thought through what could be causing it, and my guess would be that the rear brake shoes are adjusted too tightly to the drum on one side or the other. As you began to drive it felt fine, but I suspect that as you kept going part of the shoe was contacting the drum, quickly heating it up and causing the shoe/drum to bind @ a single point. When you applied the brakes the shoes made full contact with the drum and the shaking subsided.

That's my take. I'd back off the adjustment on the rear brakes and re-adjust.

I'm no expert but that does seem to make sense. Thanks.

 

[Dous]

Yep I think BFAD said it right. If you warped a drum or the brakes are way out of adjustment and rubbing it will cause shaking...same thing happened to me because of a warped drum.

 

[Kinnick]

The fact that the shaking was not present immediately, and that it seems to be affected by the application of the brakes, indicates to me that it would be an issue w/the brake shoes and/or drum.

I thought through what could be causing it, and my guess would be that the rear brake shoes are adjusted too tightly to the drum on one side or the other. As you began to drive it felt fine, but I suspect that as you kept going part of the shoe was contacting the drum, quickly heating it up and causing the shoe/drum to bind @ a single point. When you applied the brakes the shoes made full contact with the drum and the shaking subsided.

That's my take. I'd back off the adjustment on the rear brakes and re-adjust.

If that was the problem and the adjustment does the trick, I wonder if this problem could have damaged any of the parts that were replaced during the job?

 

[PitbullRescuer]

BFAD, I know you know you're sh*t and for OP's sake, I hope you're right. But when he said it started to shake as he got up to speed, and went away as he slowed, I figured it was safe to rule the brakes out. figured if it was the brakes it would get worse when he applied them. No? Just asking, not arguing.

Also, OP, ask him if he happened to separate the two halves of the drive shaft. Maybe he had it on the lift, unbolted the rear of it and the slip yoke came apart. He put it back together and didn't have it in the same position so it is now out of balance. Maybe?

 

[BigFishAllDay]

If that was the problem and the adjustment does the trick, I wonder if this problem could have damaged any of the parts that were replaced during the job?

Unlikely. If you drove 1000 miles like that, maybe, but what you did was pretty much a test drive. Worst case scenario is that you warped the drum a little bit, which could be as simple a fix as having the the drum turned.

You might ask your mechanic about doing that for you, just in case, to ensure you don't have to return a second time.

 

[BigFishAllDay]

BFAD, I know you know you're sh*t and for OP's sake, I hope you're right. But when he said it started to shake as he got up to speed, and went away as he slowed, I figured it was safe to rule the brakes out. figured if it was the brakes it would get worse when he applied them. No? Just asking, not arguing.

Also, OP, ask him if he happened to separate the two halves of the drive shaft. Maybe he had it on the lift, unbolted the rear of it and the slip yoke came apart. He put it back together and didn't have it in the same position so it is now out of balance. Maybe?

It's this part:

When I would apply the brakes the shake would actually become much less, but when I let off the brakes as I was slowing down it would shake again.

Brakes on, shake goes away, brakes off shaking comes back... with decreasing speed.

If it was a bent axle shaft, it seems to me like it would get progressively worse with increasing speed, and settle down with deceleration. The problem would be independent of the brakes and I would think the vibration would be unaffected by the application of the brakes because the entire drum/shoe assembly is rotating on the outboard end of the axle. It would seem like the brakes affected it, but it would actually be the decrease in speed. In his case, he's saing that even as the speed decreased, the problem did not go away, EXCEPT for when he applied the brakes.

RE the driveshaft, there is no reason to touch the driveshaft for an axle seal job, so I doubt that would be the cause either.

 

[PitbullRescuer]

^ that makes sense. OP, I really hope BFAD is right. Keep us posted.

 

[JWaldz]

Trust me, You could tell if it was a bent axle shaft and brakes wouldn't change the feel in it. A bent axle shaft you would notice right off the bat and it would actually get less noticeable the faster you go. It would take a mighty bent axle shaft to get the feeling your getting though. I've bent 2 now, one more major than the other and the worse was only just noticeable. I could visibly look in my side mirror though and see it wobbling at slower speeds. Higher speeds you couldn't tell. My guess is, it's not a bent axle shaft. Has to be the drum or something with the brakes. BFAD I think is on the right track with the brakes needing readjusted.

 

[Dous]

Warped drums, the mechanic probably replaced the shoes, but because they were probably sticking due to gear oil covering them the drums overheated, causing warpage.

You can easily have the drums machined tons of material there

 

[Kinnick]

It's this part:



Brakes on, shake goes away, brakes off shaking comes back... with decreasing speed.

If it was a bent axle shaft, it seems to me like it would get progressively worse with increasing speed, and settle down with deceleration. The problem would be independent of the brakes and I would think the vibration would be unaffected by the application of the brakes because the entire drum/shoe assembly is rotating on the outboard end of the axle. It would seem like the brakes affected it, but it would actually be the decrease in speed. In his case, he's saing that even as the speed decreased, the problem did not go away, EXCEPT for when he applied the brakes.

RE the driveshaft, there is no reason to touch the driveshaft for an axle seal job, so I doubt that would be the cause either.

Correct. I first drove half mile through town (all fine) then 1 mile on highway (all fine) then shaking started and got worse next half mile as I started to slow down. Each time I pressed on brake the shaking was much less. Pulled over then waited about one minute for traffic to return to town. Return trip started fine until after about half mile then shakes started all over again. Shakes got worse as I got back into town to repair shop, yet again applying the brakes made shakes much less.

 

[PitbullRescuer]

This is one instance where I am glad I'm wrong.

 

[zacattack20]

Stupid enough but you sure the lug nuts are tight. Haha. Your issue sounds exactly like what my truck was doing after I changed my rear axle seals. And it turned out my dumb ass didn't torque the lug nuts down tight enough, and it was only a couple that were like a 1/4 turn loose.

 

[Drcoffee]

So my local mechanic who I trust and has worked on my 4runner for the last 8 years, just finished the rear axle seal job on my 1997 SR5 4x4 with 160,000 miles. I made him aware of this common problem and even showed him the thread from bigfishallday highlighting what might be some reasons for the failure. The parts he used all appear correct per the thread. I took my 4runner for a drive after the job and at first it drove perfect. Then after being on the highway for about a mile I noticed a rattle coming from the back tailgate. At first I thought maybe it wasn't shut tight but then my 4runner started to shake more in the rear end and could be felt in the whole vehicle. I decided to pull over. When I would apply the brakes the shake would actually become much less, but when I let off the brakes as I was slowing down it would shake again. I came to a comlete stop then headed back to town. As I picked up speed it drove fine for the first half mile but then it started to shake again and pretty bad when I got back to the repair shop. Unfortunatley they had just closed so I left it there to address it in the morning. Any ideas what may be causing this or what may have gone wrong during the repair job. Thanks for the help.

Don't rule out the possibility that he F'd the seal job and the seals are still leaking.

 

[lpittman]

Is it possible he "unbalanced" one of the tires by accident? Perhaps he dropped it and weight fell off? Or maybe there was dirt or something inside the tire that fell out when he laid it down?

Not likely the problem - but ya never know, just throwing it out there.

I just did my rear seals and the same thing happened to me, shook like crazy. Got the tires rebalanced just to rule it out and fixed it right up.

Cheers and good luck figuring it out.

 

[Kinnick]

So I see my mechanic this morning and he was just getting back from test driving the 4runner. He also felt the shake. The right drum was very hot to the touch and it had some fine shavings in it. I could see a couple of blue hot spots so I am guessing it is warped. The shoes appeared fine and not adjusted too tight because we could rotate the drum just fine. As to what caused this I am unsure. I suggested swapping the drums from one side to the other. Went on a 10 mile test drive and no shake. After the drive the warped drum was warm but not hot like it was originally when it was on the other side. The right side drum (now good drum) was fine to the touch. They said they are going order a new drum for me and go from there. Any thoughts?