Replaced rear axle seals and now random vibrations/shaking

[zacattack20]

So I replaced my rear axle seals, and rear brake shoes and wheel cylinders this weekend. And now at varrying speeds the steering wheel will start to vibrate and then you feel it in the seats and then the whole back end will start shaking. It does it at varrying intensities at different speeds. The first time it was at about 80mph. And then it started doing it at 50-60mph. And it wouldn't do it everytime I got to those speeds. And it wouldnt always be bad shaking. Sometimes it was just vibrations and twice it shaked fairly strong. I would then let off the gas and it would slowly start going away. Anyone have any ideas?

 

[scottyb]

Possibly the lug nuts are tightened a little unevenly? I would put the 4Runner on 4 jack stands and drive the wheels to see if you can see/hear anything and locate the problem. Is there any whining or is it just vibrations?

 

[zacattack20]

Thanks for the reply. And No, there isn't any whining or abnormal noises. My wife was distracting me at the time so I was in a hurry putting the wheels on so if lug nuts could do that then it could be a possibilty.

 

[Drcoffee]

I would guess that the drums are either still affected by the gear lube or the drums are out of round and need to be turned on a lathe. It's a horrific shake when the rear drums are warped and grabbing.

 

[zacattack20]

Ok so stupidly enough I believe it was the lug nuts. Haha. Normally I have an impact wrench and a torque stick to put my wheels on but I didn't have it at the time and like I said my wife was bothering me so I was distracted when I was putting them on. Haha. But I torqued them down now and put about 50 miles on today afterwards and didn't have the issue. Thanks for the replies.

 

[scottyb]

Good to hear! On the positive side, it was a free and easy fix.:hatsoff:

 

[Jon]

We're deducting one point for that one! Next time have the wife put your tires on:sobbing: JK man, at least you didn't loose one going down the road. That could have been a bad accident. Pay attention fool! :rockthrow:

 

[zacattack20]

Hahahaha yeah I'll tell her next time to do it. And yeah that could have been bad. They weren't even that loose though. At the most, one was like a quarter turn. Most of them were tight.

 

[remark88]

I'd like to revive this thread if possible. T4R.org has been invaluable for a number of projects & fixes and now I have one that has me stumped. I have the same problem here but it's not lug nuts and it's not the brake drum (replaced it last week). Here's the whole story:

I had a leaking drivers side rear axle oil seal on my '96 SR5. I couldn't figure out how to back the shoes off the drum based on the Haynes description so I was actually tightening the auto-adjust screw. I ended up using the screw holes in the drum to force the drum off and I'm thinking this is the root cause of my problems since the drum was pulling hard on shoes that were nice & tight against the drum. But, I can't find the actual source of the shaking. The rest of the axle seal job went fine & the leak has been fixed. But the shaking started the next day. I replaced the drum because I thought I may have bent it a little, and the problem went away for 4 days. Then on the highway yesterday & today starting around 55mph, the shaking came back. I pulled the e-brake a little & I could feel shaking in the handle. Then magically after a few minutes, the shaking went away & the rest of my drive was fine. I put an infrared thermo on both drums. The drivers side was about 150F, the passenger was about 100F so obviously the brakes are rubbing, but replacing the shoes & the drum didn't fix it. Could I have bent the backing plate so that everything is just a little out of whack? I know this will most likely be guesses since this is a very odd problem, but any input would be appreciated! My next step may be finding a parted out 4Runner & buying the whole backing plate/axle assembly.

 

[chadsy]

I'd like to revive this thread if possible. T4R.org has been invaluable for a number of projects & fixes and now I have one that has me stumped. I have the same problem here but it's not lug nuts and it's not the brake drum (replaced it last week). Here's the whole story:

I had a leaking drivers side rear axle oil seal on my '96 SR5. I couldn't figure out how to back the shoes off the drum based on the Haynes description so I was actually tightening the auto-adjust screw. I ended up using the screw holes in the drum to force the drum off and I'm thinking this is the root cause of my problems since the drum was pulling hard on shoes that were nice & tight against the drum. But, I can't find the actual source of the shaking. The rest of the axle seal job went fine & the leak has been fixed. But the shaking started the next day. I replaced the drum because I thought I may have bent it a little, and the problem went away for 4 days. Then on the highway yesterday & today starting around 55mph, the shaking came back. I pulled the e-brake a little & I could feel shaking in the handle. Then magically after a few minutes, the shaking went away & the rest of my drive was fine. I put an infrared thermo on both drums. The drivers side was about 150F, the passenger was about 100F so obviously the brakes are rubbing, but replacing the shoes & the drum didn't fix it. Could I have bent the backing plate so that everything is just a little out of whack? I know this will most likely be guesses since this is a very odd problem, but any input would be appreciated! My next step may be finding a parted out 4Runner & buying the whole backing plate/axle assembly.

How many clicks are you getting when you pull your parking brake?

 

[remark88]

I start feeling the vibration after 2-4 clicks. The vibration in the handle doesn't stop if I pull more. It takes about 3-5 minutes of highway driving (and a pull or two on the handle) and it usually smooths out. I'll try it again when I leave the office today since my drive home is nearly all highway.

 

[Yoter]

I had my brake cylinders go bad while doing the axle job, even though I put zip ties on them. And after lots and lots of diagnosing that is what turned out to be causing my rear brake rubbing.
I would try replacing them I used ones from Auto Zone they were super cheap but have been doing the job fine for the last 2-3k miles
If you do go this route be careful with the bolts that mount the cylinder to the backing plate they snap really easily if you over tighten them. (they dont need to be very tight to begin with)

 

[Skidmarcx]

These trucks seem to be sensitive to the shoe clearance... I've had this exact problem and it turned out that I had the adjustment too tight... Generate heat and you get expansion which leads to pulsation... Compound the problem at highway speeds. Having warped drums just made it more difficult to dial it in, so I replaced them and I keep somewhat of a loose adjustment now

 

[remark88]

These trucks seem to be sensitive to the shoe clearance... I've had this exact problem and it turned out that I had the adjustment too tight... Generate heat and you get expansion which leads to pulsation... Compound the problem at highway speeds. Having warped drums just made it more difficult to dial it in, so I replaced them and I keep somewhat of a loose adjustment now

When you say "adjustment too tight", are you referring to the automatic adjusting screw?

On my ride home on Wednesday, I paid closer attention and could feel vibration before even one click of the e-brake. Then the problem basically went away & hasn't come back! The wheel/drum is no hotter on one side than the other. I'm going to call it shoe clearance. Maybe pulling the e-brake shifts the shoes back into the correct position. I'll definitely keep the brake cylinder in mind since it's such a cheap part. Now I have two things to check if it decides to come back. Thanks again for the useful info!