Bad Universal Joints?

[NWA_Dave]

Hey Guys- I tried searching but couldn't find anything definitive...

My 2000 4Runner has recently starting slightly jerking/lurching. Like if I'm on the highway, and I let off the gas the whole way, then give it a little gas again, it just very slightly jerks when I let off, then jerks/lurches when I put my foot back on the gas. Does this sound like a bad u-joint?

 

[shootmymime]

Hey Guys- I tried searching but couldn't find anything definitive...

My 2000 4Runner has recently starting slightly jerking/lurching. Like if I'm on the highway, and I let off the gas the whole way, then give it a little gas again, it just very slightly jerks when I let off, then jerks/lurches when I put my foot back on the gas. Does this sound like a bad u-joint?

crawl under it, put you hand on the shafts and twist, wiggle, shake and shout :girl:.
oh sorry got carried away, yeah do that and look for a broken joint, it will most likely be on the rear shaft but check both.
you have 4 joints if its a 4wd, 2 if its a 2wd.

 

[NWA_Dave]

crawl under it, put you hand on the shafts and twist, wiggle, shake and shout :girl:.
oh sorry got carried away, yeah do that and look for a broken joint, it will most likely be on the rear shaft but check both.
you have 4 joints if its a 4wd, 2 if its a 2wd.

Hey, that's distracting :biggrin2: Thank you.

Anyway, I just crawled under it, and there was no play. What else could cause the symptoms I described?

 

[scrap metal]

By jerk, does it actually lurch forward?

or do you feel a jerk? What does your shift selector do when this happens? does it move? Perhaps worn transmission mount and/or engine mounts are worn.

 

[shootmymime]

By jerk, does it actually lurch forward?

or do you feel a jerk? What does your shift selector do when this happens? does it move? Perhaps worn transmission mount and/or engine mounts are worn.

that was my next bet. i bet its engine mounts or tranny mounts

 

[NWA_Dave]

that was my next bet. i bet its engine mounts or tranny mounts

Ugh, this is starting to sound expensive...any guess as to how much for each scenario?

 

[shootmymime]

Ugh, this is starting to sound expensive...any guess as to how much for each scenario?

20-50 bucks a mount, i think there are 4 total, but not all of them will be bad, maybe 1 or 2

 

[Andy in Pa]

To check the rear shaft, put the rear axle up on jack stands. Sometimes joints can feel tight when the tires are on the ground, but once they are free to move ( tires off the ground) there is no stress on the joints and if they are loose you'll see free play in the drive shaft.

 

[csp]

20-50 bucks a mount, i think there are 4 total, but not all of them will be bad, maybe 1 or 2

It's good practice to replace all mounts even if they aren't all bad though.

 

[NWA_Dave]

To check the rear shaft, put the rear axle up on jack stands. Sometimes joints can feel tight when the tires are on the ground, but once they are free to move ( tires off the ground) there is no stress on the joints and if they are loose you'll see free play in the drive shaft.

Ahh, good point. It is parked on a very slight incline, which probably would keep them tight. I'll have to try your suggestion this weekend.

I'll also have to pay more attention this weekend to see if there's noticeable play in the shifter when it does the jerking.

Thanks guys, I'll let you know what I find!

 

[gs300tt]

If when you let off the gas at highway speeds it feels like the ass end of the truck does a little shimmy or wiggle the problem is most likely not with your drive shaft. It is moving because the rear end is moving. I would start by checking the lower and upper links on the rear and then the panhard bar. I would put money on one or more link bushings being bad.