low speed vibration

96 3.4L V6 automatic 2wd, 300k miles

The shop replaced the J-joints and transmission mount today to address a vibration I'm getting at ~20mph for months now, particularly when going uphill but somewhat noticeable when coasting or braking too. They said the U-joints were locked up and worn, and the transmission mount rubber was worn which I had noticed before, and they showed me all the parts they took out. I had suspected U joints and had directed them that way to check out unless they saw something else.

On driving away I found the problem is still present, and not only that, it's shaking a little at idle.



I looked underneath, and the big bolt in the middle of the new transmission mount is not tightening. The only thing I had big enough to test it with was a crescent wrench. It tightens for part of a turn and then goes loose again. Is it supposed to tighten like any bolt or is it there for some other reason? The 4 12mm bolts surrounding it feel tight.

It's this one:
https://www.oreillyauto.com/detail/.../v/a/8216/automotive-truck-1996-toyota-tacoma

They said the center bearing was ok and left it.

If I push on the drive shaft at the center bearing I get a little smooth play, less than 1/4" in up/down and side/side. All 3 U-joints have a slight wobble/clunk sound if I grab and shake the drive shaft by them, nothing loud but it's there. Is that all normal?

The old U-joints were gunked up and felt more solid, but maybe that wasn't good if at least one was locked.

Recently I replaced the oil, transmission fluid, coolant, rear differential oil, and power steering fluid at home, and the levels are all good. A year ago got new spark plugs and one coil.

 

There should be zero play in u-joints. If you’re sure there is and that’s causing your clunk when moved by hand, they need replacement

 

I checked again to be sure. I lay down, reach under and grab the shaft with one hand by the front U joint, shake it good (but one handed, and I'm strong but not a beast), and from the U joint I get a small but noticeable amount of hard-feeling play (it feels like something metal that fits together loosely) with light clunking sound. Same with the rear U joint. What you say sounds right because I have a hard time imagining that it's supposed to be able to be clunking even that small amount as it hits bumps down the road or whatever causes them to move while driving. You're saying I should not feel that at all? Would these new U joints be bad (seems strange?), or would they just need to be adjusted? It sounds like I need to drive by the shop tomorrow and show them.

The middle U joint it turns out does not give that kind of clunking play, just some from the center bearing next to it, which feels like soft play that would not wear something out quickly, with a slight squeak sound of rubber or plastic, which I think is ok?

Also, I can grab and rotate the drive shaft like one degree or so, with a softer noise but I can hear the metal. Normal?

They did mention these U joints are expensive @ $78 each and that they usually cost like $20, but that these have a pin in each one that is required for this model, or something like that? The part on the invoice seems to be the Toyota part,

$60 04371-60070 Universal Joint

04371-60070.

In a previous thread, someone mentioned this drive shaft has tapered...something. I forget the word. I mentioned that and the shop said that's no problem, but could it be?

 

In case it helps at all, attached are the new front, middle, and rear U joints.

 

Honestly, I'd suspect wheel bearings or rear diff bearings if you've had all that done.

I had a chirp, as well as a very slight vibration while turning the wheel, at mid speed (50-60) going uphill. Ended up being the front wheel bearings.

The carrier bearing should have some play to it, that's ok.

You won't be able to accurately inspect the u joints unless you remove the drive shaft from the truck. The drive shaft will have some rotational play (essentially backlash), but in order to assess the u joints, you gotta take the drive shaft off. But the shop really would had to have fucked up to ruin new u joints.

Toyota's have tapered yokes- which makes the traditional u joint c clamps difficult to use.

Is this is a 5 or 6 lug truck?

 

The wheel bearings were repacked 4 months ago by the shop. I assume they would have noticed bad bearings then?

Differential bearings I've never heard of until now.

Maybe something in the front axle? It feels like the vibration is in the middle or front of the truck, but I could be wrong.

 

There are pinion and diff carrier bearings.

Being that you're saying re-packed, I'm going to assume 5 lug, as the 6 lugs have sealed wheel bearings front and rear- no opportunity for repacking (if a shop charged to re packed sealed bearings, you should report them to the BBB). Unfortunately, with bearings it's often best to go through all the lower cost items, (all bushings, etc.) to rule them out before spending money on the big ticket items. Unless the bearings are really bad.. then they are obvious.

Often times though, shops will just put the truck up on the rack and take their best guess without driving the truck around (which takes time). I had three shops (one very regionally reputable, the others locally reputable) attempt to diagnose my eventually bad front wheel bearings. They tried to suggest other things which I knew were not issues. But they didn't drive the truck themselves in any of those cases.

 

The wheels have 5 lug nuts, if that's what we're talking about?

The shop guy has hopped in the truck with me before to duplicate a problem, so I'm counting on being able to do that tomorrow. Going uphill at 20mph it's very obvious.

 

Fwiw, the BBB is nothing more than yelp for the pre-internet age. It’s not a “bureau” at all, just a private ratings business. Local police or small claims for a fraud case would be better

 

change the motor mounts aswell.
https://youtu.be/g_4DiywsSbk

 

New symptom! - I jacked the left front tire off the ground and wiggled the tire. When I hold with one hand on the top and other hand on the bottom of the tire and try to repeatedly tilt it in/out, I get a small clunking. The lug nuts are tight. Is that a wheel bearing replacement sign? The other 3 wheels feel solid with this test.

To be fair to the shop, I did point them towards the drive shaft as a possible culprit. The U joints were in need of replacing, so I'm not mad about that. As long as what I described as far as wiggling the drive shaft in post #3 of this thread sounds fine to you guys, I'll call that part good.

 

I might have them do that too. It was vibrating a bit at idle as I picked the truck up from the shop today. Who knows if they dug around in there and didn't tighten something but I'll have them check the engine mounts. I believe they're original.

 

I would do it myself I read that you changed a lot of stuff, just do it yourself. Personally I trust no mechanics. Always use oem. Try the easy stuff first change the plugs, clean maf, check air filter, clean tb and iacv.

 

Would I just need 2 front engine mounts? Other parts here usually not necessary? No rear mounts?
https://parts.toyota.com/a/Toyota_1...D/63075570__6725706/MOUNTING/675460-1107.html

 

yeah just the 2 motor mounts, toyota calls them insulators

 

change ur ball joints aswell

 

This could be attributed to worn ball joints, bushings, or wheel bearings. I'd suggest replacing them in that order until the wiggle is gone.

 

Wheel bearing shouldnt clunk when wiggling from top and bottom

 

Depends on how worn they are. A buddy of mine ran his wheel bearings almost to the point of failure. The wheel moved in every direction.