Vibration @ 30-40mph after 5100s installed @ 1.75

It goes away when it's in 4wd, but comes back rather quickly when you take it back out of 4wd.

 

Im almost wondering if it is my tires, because today I haven't noticed it at all.

 

Just yesterday I installed my 5100s at the 2.5" setting with a 1" block and Firestone Ride-Rite air bags in back.

The ride is awesome (replaced the stock TRD sport bilsteins w/100k) but I am getting a fairly noticeable vibration between 20-40mph. I had it aligned immediately and the tech said he had no issues and got it spot on and it does track nice and straight down the road.

I just went for a quick spin and put it in 4x4 and the vibration goes away and then comes back immediately when I switch back to 4x2. Sounds like I'm screwed to the tune of a new front diff bearing eh? How involved is the fix?

 

I'm really sorry to hear that. I looked at the FSM on tearing down the front diff and it required too many parts for me to do. The bearing (from what I hear) is about a $90 part. But if you don't have all the specialty tools to replace it yourself and have to pay someone, it costs more in labor than to get a new one. New front diff costs $1,700 (from dealership, but I hear you can save about $400 or so from online sources). Install labor is 4 hours. Mine cost a total of $2,200. But even though I have over 90K miles, I still called and complained to Toyota Corporate. The 15 minute phone call was worth it. They never even looked at the truck or anything, and they're splitting the cost with me 50/50. I already sent them a copy of the bill and am now just waiting for a reimbursement check in the amount of $1,106.

I am curious as I've been keeping track of how many miles have gone by before someone discovers this problem. How many miles do you have? (currently, the people I've tracked have 27K, 44K, 58K, & 63K (this last person had one replaced twice under warranty so this was his second mileage number). And I first discovered mine at 88K miles.

 

Thanks for the info. I tried driving down the freeway and switch my truck into 4wd and the vibration went away, then put it back into 2wd and the vibration was back. Now my question is COST? and I bought the truck used less than a year ago and also got the 100,000 mile warranty, will this be covered? Will they try to screw me since I changed the front shocks? And lastly, If I put it down a notch or back to stock height, will the sound go away? What the crap, all I wanted was to level the truck out and I screwed myself I think. Damn Toyota is a pain. I have had many minor problems with the truck and now a major one! I may have to buy American oh yeah I have a GMC, not running well, but at least it has a good excuse, its 40+ years old!!!

 

So I think my diff is screwed. Did your warranty run out when you had to have it replaced? Did this occur with a lift? I have 100,000 mile warranty and am wondering if it will be covered. Also wonder if the will try to screw me on the warranty since I changed the shocks? Thanks for the info!

 

Bump

 

Do you have the rear TSB or a AAL?
I didn't have a vibration with just the front set at 1.75". A vibration did pop up once I installed the 1.5" AAL. I'm pretty sure the driveshaft carrier bearing spacers will fix this problem.

 

It just turned over 100k. I had an extended warranty and just had some transmission work done, but i waited until it was out of warranty to lift it, doh!

did you explore the option of removing the diff from the truck, paying someone to do the bearing and then reinstalling it yourself? Are there any specialty tools required to get the diff out, or just to tear it down and replace the bearing?

In fact, if you still have the service manual doc for the job, it would be really helpful to post it here. I have a feeling that this thread is going to get more and more action as the trucks start turning 80/100/120k mi....

 

Sorry guys that it took so long today to respond. Sorry about the long post, but I know several of you wanted to know exactly what happened in my case, so I'll try and answer all of them.

First, I was out of warranty when I diagnosed the problem (power train warranty was out at 60K miles which occurred well over a year ago or more) and I first discovered it at 88K miles (when I first put on the AAL and 5100's...prior to that I was all stock...no rear spring TSB thus the need for the AAL). Then I attempted many things to try and fix it. I tried taking my 5100's down from 1.75 to .85. At 1.75, it was audibly grinding and I'm sure you could hear it if I drove by you while standing on the side of the road. So I lowered it to .85 and it was better, but the vibration was still there. Then based on a recommendation by someone on another forum, I installed a 1" diff drop which seemed to completely eliminate the vibe. Installing the front diff drop brought the front axles back to the stock angles. But, a few thousand miles later I got new tires. Got rid of the BFG AT KO and replaced them with Michelin LTX AT2. Suddenly, the tire tread was so smooth and quiet on the road that I could feel the vibration again. I had thought it was gone, until I got the new tires. Turns out I just couldn't hear/feel it because of the tires. I probably had the vibration for thousands of miles before installing the 5100's, I just didn't know it!

So why didn't I try and pay someone to tear it down? The answer to that was mainly because I tried putting up with it for a couple of weeks. But my family and I were heading out on a 2K mile trip to visit family and I was really worried about it failing on the road (can you imagine the cost then with towing and a rental). So I made my decision 3 days before the trip to get it fixed. I didn't have time to leave the truck with someone to tear it down. Plus I heard it may take someone close to 20 hours to tear it down and replace it. With local labor rates running around $100 per hour, it was almost just as cheap to swap out the front diff with a new one (this is also why toyota does it this way for warranty).

If you're still under warranty and have replaced the shocks, I wouldn't worry about it too much. The first person over on TN to discover this problem in March 2007 had his replaced twice under warranty and he also had a lift (he's the one that posted first in my thread below and he's the author of the second post). It's just going to depend on the dealership. If one gives you a bad time, try another one.

If you're out of warranty like I was, call Toyota Corporate and complain. I called them on a Wednesday while my front diff was being replaced at the dealership. By Monday they called and said they were splitting the cost 50/50. They're cutting me a check to reimburse me for half of the total cost.

So going the route I did was better than paying someone to tear it down and replace the bearing because it only cost me $1,106 after Toyota's reimbursement. If I'd paid an independent shop, I would have had to pay the whole thing.

If you want to read my thread and all of what I summarized above, you can find it here:
http://www.toyotanation.com/forum/showthread.php?t=335992

Here's a quick reference thread on TN for "Vibe" that cj put together to help people diagnose the front diff vibe:
http://www.toyotanation.com/forum/showthread.php?t=338228

And I've attached all 3 sections of the manual related to the front differential.

 

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I have the same problem....

 

Is the problem only the bearing ?or something else?, I think, I'm dismantle the diff. and change the bearings...

 

Could it sound like an intermittent speak that goes away once you press the brake pedal?

 

the vibration goes away , in H4 (4x4),in 4x2 I have the vibrations...25 to 35 mph

 

exactly what happens with mine. usually at 30-40mph.

 

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Finally got to shop with truck made shop foreman drive it after the other mechanic said they didn't feel it. Foreman felt it. They called next day and said its rear diff. Its under warranty and will be replaced for free along with recalled accelerator pedal. We will see. Maybe I will end up with new rear and front diff. That didn't say anything about the shocks and leveling of front yet!

 

dont let them do the accel pedal they cut the pedal shorter tell them not to do it