Tacoma shaking and vibrating 60-80MPH

Hello all. I have a bit of a toughie.

I have a 2002 Tacoma V6 double cab. Its a PreRunner (4x4 hopeful).

I have a vibration at 60-80MPH - it starts and goes away every time at that speed without fail. I brought it into a shop today because I am stumped, but turns out the shop is also stumped. The guy said he's been doing this for 15 years and never seen anything like it. Shake has been there for the last 10 years maybe. It was my dads truck, he died, then it went to my mom who gave it to my grandpa, grandpa gave it back to me as my first car 5 years back. My grandpa gave me the truck and told me there was a vibration at 60-80MPH back then, and I've just toughed it out ever since. I'm getting really sick and tired of everything in the car jiggling and bouncing up and down though because for the foreseeable future I'll be doing a LOT of highway, so I am looking for recommendations.



List of things I've done and their impact:

• Upper/Lower ball joints - No impact

• Inner/Outer Tie Rods - No impact

• Front Coils and Shocks - No impact

• Tundra Brake Upgrade - VERY Minor improvement (Think I had warped rotors)

• Center Driveshaft Bushing - VERY Minor improvement

• Single Piece Driveshaft Conversion (a few months after driveshaft bushing replacement wore down) - Major improvement at sub 60 speeds, No impact on 60-80 vibrations

• "Axle Wrap Be Gone" mod (here on TW) - Major improvement at sub 60 speeds, No impact on 60-80 Vibrations.

• Transmission Mount - No impact

Possible Suspects

• Transmission
• Rear Leaf Packs
• What do you all think?

Suggestions so Far

• Rear Brakes
• Bearings in general

Shop guy said today he doesn't think it's suspension because its only speed related, not bump or environment related. Could be blacktop, concrete, curvey, straight, don't matter, just the speed. My grandpa did have the transmission "Rebuilt" (I don't know if it was actually rebuilt or just replaced) at 140K a long time before he gave it to me, I wonder if they screwed something up then? He never really drove the truck, especially not highway speeds because he just kept it around for me, so if they did screw something up he wouldn't have noticed for at least a few weeks and might've just thought something else broke.

If it is the transmission... Maybe it's time to do that 4x4 conversion...

Any thoughts?

 

Rear brakes would be worth trying.

If you haven't done rear brakes before, you NEED the spring tools. When I was younger I thought I could do it without them, and you can, but it SUCKS.

 

I noticed your list of fixes does not include any bearings. For example, wheel bearings, or the pinion or carrier bearings in the rear differential, or output bearings in the transmission.

I doubt a bearing on its way out would last as long as your issue, but who knows.

Also I know you’re not thinking suspension, but how are the control arm bushings? Motor mounts?

Does it chew up tires? Alignment and wheels balance OK?

I don’t see a smoking gun in your response but maybe these questions will help others help you.

 

I haven't done any kinds of bearings... that's definitely one I'll add to the suspect list.


Control arm bushings are OK the shop guy said, I haven't actually checked them myself. I should and then post it here. Motor mounts and alignment are good, and I just had all four wheels road force balanced at discount tire last week. Tires wear even too. It's all the symptoms of an out of balance tire, but without the tire being out of balance.

Good questions. I tried to answer everything in my post, but I forgot some things, I appreciate the help.

 

Okay. Yeah they are the factory brakes still, but with new shoes. Should I do the whole rear brake assembly (new drums and all)?

I'm all about using the spring tools if it helps, its too cold up here in Michigan to be diddling around outside all day LOL!

 

I chased a vibration for a long time.. my rear drums were outta round. I think they became that way from either a bad turning job at a local shop (unlikely) or the shoes were over adjusted. People will say that you can't over adjust them via the parking brake, but I believe otherwise. It is possible to continue to turn the star nut past the point of correct adjustment, and the shoes will excessively drag until they wear themselves into adjustment.

I have that job down to an hour ish, but I've done it a few times. Wouldn't wanna do it with cold fingers for sure.

 

Thats a good idea. I have never done the rear drums in the 5 years I've had it, and I believe my grandpa only ever had the shoes done and adjusted. The shoes are fairy worn, but definitely got a lot of life left in them, so if I were to just buy the drum and give it a whirl on the eway that should tell me if that was the issue right? before I go tearing apart the whole rear end that is. Correct me if I'm wrong, im a Gen Z'er so I don't know much about drum brakes, but drums are the drum brake equivalent of rotors?

 

Yeah it gets real chilly real fast that one I'm certain of!

 

Drums are the rough equivalent of the rotor in a disc brake setup, yes. But, considering the price of the parts in question, I would highly suggest just replacing both. It's not really good practice to replace just pads or shoes without also replacing the rotor or drum.

 

Awesome. I'll go ahead and put in an order at advance auto, seems cheap enough to do regardless. Could an out of round drum cause a vibration even when the brakes aren't applied? Since the vibration isn't related to the breaks I feel like it couldn't be the drums, but they're definitely due for a replacement anyways.

 

I suppose you could try this first- get the rear axle on some jack stands (obviously chock the front wheels so it doesn't roll anywhere) and rotate each wheel and see if you can feel anything abnormal. When mine were out of round, I could feel the shoes drag at certain points in the rotation. I think it was the drag/no-drag/drag cycle that would cause the vibration.

 

This happened on my 4Runner around 50MPH. Entire thing would shake like crazy. Ended up going away after new tires. Old tires looked fine, just low on tread.

 

sounds a lot like mine, did you get new rims too? I have been reading that those could also be suspect. they're still the original oe steel ones.

 

I’ll guess the rr brake cable is broken, too. Use oe, only.

 

Actually somehow my brake cable is fine (for now). Most of the truck's life it didnt have a cabin side brake cable, just replaced it over christmas break (uni student). Drivers side rear cable is always super tight though, like it wont actually release.

 

nope, they were factory wheels, but I wouldn't rule that out in your case

 

How old are the tires? Even if they look good and have good tread they can cause vibration. Also check your steering rack bushings, if they are shot it will cause excess movement of the rack.

 

Tires are pretty new, I got them in august. It's done this shaking thing through three sets of tires, but whats weird is my tread has always worn even (no cupping and such). Its an awful shake, sometimes it feels like your coming out of your seat.

 

if only it worked on these shakes LOL