If you read the thread you know whats wrong. Whats your question?

 

i would try some 2.5 degree shims and see what happens. if not fully satisfied try the carrier bearing drop?

i have the same issues, mine are slight. i have a long bed single cab and have 4crawler 3 degree shims on order.

 

This wont help.

 

I have the same AAL and no vibes. Maybe it is just with the 4wd's?

 

Its a front diff bearing issue, so yes this only affects those with 4wd. Also the AAL isnt causing his issue.

 

Thanks cj99si, I'm finally getting past the point where you pointed out the problem and how they fixed yours (I'm at page 20 of 34 and read your other "its a lift DC LB" post too). I did check the play in the shafts yesterday and they move maybe 1/4 of an inch!!!!! Looks like these front differentials are all going to go bad before hitting 200K miles. Sucks when there's no warranty to cover them.

Part of the reason I started a new thread was to point out that it's not just "lifted" trucks going 3". Just adding an AAL or getting the rear leaf TSB done then wanting to level the front will cause the problem to appear. I really wonder if I go back to stock height and remove the AAL (don't want to be sitting nose down), how long will the front diff bearings last before it craps out on me anyway? I'm at 88K miles now. That likely means that there's no way they'll last till 160K miles.

I'm still looking for someone to answer my question though. You said in one of your posts that putting it in 4WD puts pressure on the loose bearing which caused the vibration to stop. No disagreement from me there. What I did ask was which part of the 4WD engages first? Based on your observations/theory, it must be that the front differential immediately engages, and then while the 4WD light is flashing then we're waiting for the transfer case to lock up. Can anyone confirm that's the order in which the 4WD engages? Because the vibe goes away before the 4WD is completely engaged.

And lastly, what to do short of fixing the front diff. I guess these are my options:
1. Live with it until the bearings finally go out the rest of the way and replace them at that point.
2. Try lowering the front down to the .85 setting and see if that cures it (and what kind of rake that leaves me with).
3. Remove the AAL (go back to relying on the timbrens 100 percent of the time) and set the front to 0 (or is .85 actually the same as stock height?).
4. Move to the north pole and leave it in 4wd all the time...nah.

 

My truck has the vibe again since I installed the 5100's recently. The thing I have noticed is, I can only hear and feel the vibe when the truck is cold, like first thing in the morning on the way to work. Once the truck gets up to normal operating temperature, it is smooth as glass. It really doesn't bother me like it did when I first lifted my truck...maybe it is because it is older now...:lol:

 

I know you removed your lift, but did you recently "re-lift" it? Or do you have the 5100's set to stock height and have the vibe that way too?

I'm still not sure what I'm going to do at this point. The pulsing grinding noise really does sound bad (sounds like a dry bearing). I wish I could just replace the bearings because I absolutely love how smooth a ride it is now and I could use the clearance. My lower engine cover has quite the dents in it from traveling off road. Plus with it set at 1.75 with that AAL, I feel like I'm driving a cadillac compared to the old SR5 setup (but then maybe the 5+ years of driving on those SR5 shocks was just too much)!

My current dilemma...do I take the time to try out the .85 setting and see what the rake looks like and whether I still have the grinding noise?

 

Thanks Dan. I just took a look at your build thread. I think I'm just in worse shape because of my mileage. Having over 88K miles, my bearings really sound bad. I cringe just driving it now. I can hear them at 5 mph with the radio off (and windows up). I'm guessing they make the noise over 50 mph, but I can't hear it once I get over 50 due to the wind/tire noise. All-in-all, they can easily be heard with the windows up from 5-50 mph.

Looks like I'll be lowering it down to .85 on the front (leaving the AAL in) to see if that'll remedy the grind. At least it doesn't cost anything to change the settings and can be done in 2 hours (took me 1 hour to do the driver's side once I figured out the trick by detaching the sway bar).

Now I just gotta find time to do it! Daughter's softball games start this weekend. I'll post back here with the results after I get it done.

 

I think it's the carrier bearing. I put washers in to drop the bearing down some, but this gives some vibes around 20mph. If the washers are out I get a sound like a dry bearing. This is more apparent on cold mornings.
I'm still adjusting/tweaking to minimize both.
Have Toytec adjustable coils up front with 5100s giving around 2.5" lift. Supersprings in back.

 

Okay, here's the update and final product (along with some stats for those interested).

I lowered it down to the .85 setting today. I can still hear the grinding when it's cold, but not as much after driving on the freeway (as noted above by 08TRDOFFROAD). After driving awhile, it becomes more of a buzz type vibration in the gas and brake pedals...plus a mild mud tire tread-type sound.

I then thought maybe I would try it at the 0 setting to see if it went away completely. After taking one apart and then measuring it compared to the original OEM shock (why I didn't just do this when I went to the .85 setting, I don't know:headbang. Anyway, in measuring the two it appears that the lengths and settings are almost identical at the .85 setting. So maybe this is all a result of a stiffer shock (my OEM shocks were shot) or maybe it was happening before I did any of this and just didn't notice it because I wasn't looking for it???

Anyway, I'm leaving it at the .85 setting and will just ignore the sound for now. Before I show the pics at both .85 and 1.75, I thought I would share some measurements. I measured from ground up to the bottom of the fender directly over the wheel center. Remember, I added the Wheeler's 1.5" AAL in the back too, and I have the tonneau and 2 60-pound bags of sand back there:

And now for the pics...

First the 1.75 trial:

And the final at .85:

Honestly, I can't tell the difference looking at the pictures!

 

I forgot to mention this in the PM I just sent you, but have you thought about trying a diff drop kit from Toytec. They can signigicantly improve CV angles, which I think contributes to this vibe. I have been wondering about doing this myself. While my CV angles are not bad at 1.75" I am wondering if I add the Diff drop if it will lower the diff enough to eliminate the diff vibe because it will be very very close to the stock angle, and when I was stock I did not have the vibe at all...I might just have to order one and try it.

Here are some pics for comparison of the change with a 3" lift.

Before:

After:

 

You know I've been meaning to read up on this. After looking at Toytec's site, for $30 I might just try it. I have noticed that the vibration does go away on hard right turns where the left wheel comes up and reduces the angle. And now I'm glad I took those measurements above. From my stats, the .85 setting raised the front by 1" on the right and 1 1/8" on the left. So I 1" differential drop should put me back to the original angle! So I guess I'll give it a try and report back. I do have to wonder though...with how bad the vibe is with a 1" increase in the angle, was I feeling this before but wasn't aware of it because it came on over time?

 

UPDATE:
I took 08TRDOFFROAD's advice and installed the differential drop yesterday. Setting the 5100's to .85 raised the front 1 inch and installing the diff drop essentially placed the front diff at the same angles it was with the stock shocks. After driving it all day today and testing it out, no more vibe.:chug: Can't hear it, can't feel it.hyeah:

So a big Thanks goes out to ya! You da man!:thumbsup:

Too bad I could feel it at .85 because I would have loved to put them at 1.75 for the ride quality and then have the drop to put it into the same angles as the .85. But that would just bring back the vibe.

 

UPDATE:
I took 08TRDOFFROAD's advice and installed the differential drop yesterday. Setting the 5100's to .85 raised the front 1 inch and installing the diff drop essentially placed the front diff at the same angles it was with the stock shocks. After driving it all day today and testing it out, no more vibe.:chug: Can't hear it, can't feel it.hyeah:

So a big Thanks goes out to ya! You da man!:thumbsup:

Too bad I could feel it at .85 because I would have loved to put them at 1.75 for the ride quality and then have the drop to put it into the same angles as the .85. But that would just bring back the vibe.

That is good news!!!! :clap:

I am glad I could help, that is the point of this forum. To get people to put their heads together to come up with a solution to a problem! hyeah:

I will be ordering one for my truck shortly, as tomorrow is payday!

I suspect I am going to see similar results installing one on my truck with them at 1.75" where my vibe is intermittent and doesn't sound like it is near as bad as yours was. I will keep you updated on the outcome when I get it installed. :thumbsup:

 

To be clear, a .85 setting up front and a three inch drop kit from toytec = no vibe? And so the cv angles are now close to stock? Good stuff if I'm following this right.​

 

To be clear, a .85 setting up front and a three inch drop kit from toytec = no vibe? And so the cv angles are now close to stock? Good stuff if I'm following this right.​

The diff drop kit 05moose and I have been discussing is only a 1" drop. It is intended to relieve the stress put on CV's after installing a 3" lift. But in 05moose's case, because he is only running his 5100's at .85" of lift the 1" drop kit allowed him to return his CV's to the stock angle and eliminated the vibe coming from his front differential.

 

Ok. Yours when installed will bring the angles back pretty close to stock then, but not as close as moose's. Very curious to see if that eliminates your vibe even though from what I understand your vibe isnt that bad. Nonetheless still present. I too have a very slight vibe and am going to chase it down. I am chalking it up to M/T tires right now but getting ready to switch to the summer setup, and am gathering info. So thanks, moose, 08offrd, and cj99si for messin' with this.

 

Well, this is one of the easiest vibes to trouble shoot. Find a smooth straight stretch of road where you feel the vibe and switch to 4wd. If it instantly goes away, then this is your problem.

I'm guess the 1" drop kit will work for 08TRDOFFROAD too. It sounds like his vibe at 1.75 is similar to what mine was at .85. The difference between the two is probably mileage (he's around 30K, I'm almost at 90K). I'm positive that as he gets higher mileage on his truck, the vibe will appear at the 1.75 setting (along with a lot of other people's too). Obviously, these bearings are wearing even if we don't feel it at the stock angles, plus they're put at those angles each time we hit a bump or go around a turn. I did notice before putting the drop kit in that when I'd go around a tight right-hand turn, the vibe would disappear because it would bring the left wheel up...leveling out the angles a bit.

 

Moose, how involved was the Diff Drop to install?

 

It is not extremely involved. I have done it once before when I had my 3" lift. It can be completed with simple hand tools and a floor jack...here is a good write up on the install.

http://www.tacomaworld.com/forum/2nd-gen-tacomas/53991-diy-how-install-toytec-diff-drop-pics.html

 

Good information....Thanks!

I presume that since I'm using the Silver-Fake-Skid Plate, it doesn't have to be re-worked for fitment since I'm using it installed over the Black-Functional-Skid-Plate, which has to be reworked to fit?

 

The plate shouldn't need to be reworked like he details in the write up. I was able to get mine back on without issue the first time I installed the diff drop. Also you are correct, there should be no alteration required to the TRD skid.

 

^ x2. And just to be clear that even in the write-up, the holes he's talking about modifying are in the rear skid plate anyway. The front skid plate wouldn't be affected (once you use the square spacers provided in the kit).

Just a little advance notice...Toytec stamps the nuts to provide resistance. It's a long haul cranking them tight while holding the adjustable wrench on the nut. Next time, I'd pull out the air tools to save a lot of cranking time.

 

Well, got the Wheeler's 1.5" AAL installed and the 5100's (front set to 1.75). The ride is soooo much better than stock. No more bouncing on the bumps on the freeway and side roads. Can't believe how much they absorb the road. All around a huge improvement!

Now for the downside. I have to read through the 35 page vibe thread. I can hear/feel it easily around 35 - 45 mph and it can't be heard/felt once past 50 mph (sounds like I'm driving with MT tires instead of AT tires). I guess it really is hit or miss just like 08TRDOFFROAD said. I really needed that AAL to help out with the firewood hauling. I guess I would have had the same problem with the rear-leaf spring TSB if I'd had it done and wanted to level the truck.

I'll have to read more on that thread, but I noticed that a lot of people thought it had to do with the driveshaft. But that just doesn't make sense. It instantly goes away when switching into 4HI (like a light switch, turn it on, turn it off). BUT, it still does it if you switch into neutral and coast which takes the load off of everything (unless you're in 4wd then it doesn't do it even in neutral). That leads me to believe it definitely has to do with the front differential or transfer case.

I can't remember if it was Fortech or someone else that explained what's happening when you switch to 4WD, but I did find it interesting that the vibe goes away when switching it to 4WD EVEN IF it never locks up! I was driving on a straight-away stretch on dry pavement and couldn't get it to lock up, but the vibe went away anyway. So what's the order in which the 4WD system engages? Transfer case goes immediately based on the switch then we wait for the solenoid in the front differential...or the other way around?

Transfer case goes in, the front actuator/coller for the axle is what takes time to engadge!

cheers
Warts

 

Great news! Raise it up a bit

 

I thought I'd give an update since it appears I had more of a problem than I was aware of. With the recent purchase of new tires that are so much quieter, I now can feel/hear that my vibration is still there.:headbang: I guess the tread on the BFG AT KO's was rough enough to keep me from feeling/hearing it. So I'm now convinced it was there all along (even before I installed the 5100's), I just couldn't hear it. Think about all those running mud tires that aren't aware that they have the problem too.:ugh3: But it's only bad around 25-40 mph now. So the diff drop did help. I can't imagine what it would have felt/sounded like with these new tires and the fronts set to 1.75!:yikes:

I will say that I'm confused with this a little based on what Warts said above. But maybe someone can confirm my thoughts on this. CJ said his was the driver's side that went bad. And we know it disappears when popping it into 4wd. It goes away after the transfer case engages. And since it's gone before the front actuator engages, does that mean the front actuator is only locking the passenger side to the rest? Is the driver's side directly connected to the front driveshaft going to the transfer case? Is that why engaging the transfer case alone eliminates the vibe?

Maybe someone can give me a better explanation so I have it clear in my head how it's working. And I can then be better at helping others with diagnosing this problem. It is interesting to note that when I'm driving at 30 mph or so and it's really bothering me, I can sometimes switch it to 4HI to eliminate it then switch back to 2HI and it stays gone (but only sometimes). Almost like the bearing is just getting misaligned or something. Must be the play in the bearing causing all these problems??

Going to be heading up to Whidbey Island, WA, here in the next couple of weeks to visit family, so there's a couple of thousand more miles I'll be putting on the bearing. I sure hope it lasts. And I'm sure someone's going to tell me to just get louder tires.:lol:

 

I had the same issues with my 07 double cab 4wheel Taco as 08trdoffroad. Removed my Revtec 3" spacer with 1 1/4 rear block and went back to stock. Problems all went away mostly. I never felt the truck was as good as it was before the lift. I always thought I could stilll feel the vibes but it was so mynute, I wasnt sure if it was in my head. Year later I installed billy 5100's all around set at 1.75 front and 1 1/4 blocks in the rear. Truck sits level. I really think the vibes are worse and the truck is not as smooth as it was with the 3" lift. Tired of screwing around with it. I've left it as it is with the billies set at 1.75. So after reading this thread, I just installed the diff drop. Truck rides really smoothe. Little little vibes up to 20mph then really smooth up to about 55mph. At 55 60mph truck has some vibes.....but its a smooth consistent vibe...not a in and out harsh vibe. Hope Im making sense here. my question is this... before the diff drop. Truck was pretty quiet but didnt ride real smooth at any speed and had strong vibes at slower speeds. After diff drop...truck is really smooth everywhere but i can almost hear the vibes or front diff making noise. It sound like I have an aggressive mudder on the truck. I like the way the truck rides now but am cocerned about the noise. Should I leave the diff drop on or remove it? SORRY FOR THE LONG POST. THANKS

 

I have my 5100's set @ 2.5 with no aal. I dont have any vibrations so does this mean I wont get the dreaded vibes after I add an aal?

 

I just means you won't get the front differential vibe. Already, you're ahead of the game. Whether you get the rear vibes, only one way to find out.

 

Took truck in today for some maintenance and talked with the service rep that I've known (and trust) for 5 years now. He's got a taco too (gen1 for offroading I believe). Anyway, he said they've only had a couple of Taco's come in to replace the front diff under warranty. None that were out of warranty. They did the swap like cj had done (just replace with a whole new front diff rather than tearing it down). He did mention, though, that they're replacing A LOT of the front diffs due to those bearings on the Tundras. Something for lotust to watch out for.

 

Dana_15 actually traded in his Tundra for a Frontier because of ongoing problems with the front differential gernading.

 

Wow really!.....the forest green one right? Also, I didn't think we were allowed to down grade to a Frontier after owning a Tacoma!

 

Yeah, I think it gernaded for the third time and he didn't want to go through the hassle of getting it fixed again. Traded it in to the Nissan dealership with gernaded front diff and all. Toyota wouldn't work with him to get him into a Taco, and Nissan would to get him into a Frontier so he went that route.

 

Geez! I just took a look at Dana's thread on that. Yeah, 3 fronts in 15 months! Sounds like Toyota has a real problem with their bearings there.

I now notice mine is worse after being driven longer. And if you missed what I said before, it's really interesting to pop it into 4Hi for a couple of seconds and then back to 2Hi and have the vibe gone for a little bit. I sure do hope it holds up on the 2K mile trip coming up in less than a week. I'm keeping my fingers crossed. At some point, I'm just going to have to break down ugh3: bad choice of words) and look into the cost of having someone tear down my front diff versus buying a new front diff and just swapping it out myself. Either way, it's going to be a big chunk of change.:headbang: