FJ62 vibration at about 55-65 mph

[cruiserbrett]

Alright, I finally got the FJ62 back together(I bought it with the head off so I have no idea what it drove like before)

After a bit of timing issues, and some other minor details, it drives fine, but it has pretty noticable vibration at about 55-65mph that is present only when I give it gas... coasting it seems to be not there, but as soon as I give it gas, its back.

I am going to do u-joints on it in the next couple days, but aside from that I have no idea where to start looking...

-Brett

 

[sanjuancruiser]

you might look at the front pinion bearing in the rear axle they're known for causing that. I had one the race was turning in the housing and only made noise when the truck was cold and would go away after driving awhile on the highway. The race would heat up and expand and stop turning in the housing-wierd .

 

[dogboy2]

Sounds like it could be driveline/u-joint related. My guess is that your driveshafts may need to be straightened and balanced -- at least this is a good place to start along with the u-joints. All of this can be handled quickly and relatively inexpensively by a reputable driveline shop. Use OEM u-joints and let the shop put them in. While the u-joint replacement is not mechanically difficult, it is a major PITA without a press and jigs to hold the driveline in place while pressing. A good shop is THE way to go on this, trust me. I found out (after the fact on my front driveline) that most repair shops send their drivelines out to specialty driveline repair shops when their customer's rigs need this service performed.

-dogboy- '87 FJ60

 

[lowtideride]

i had a bad u-joint doing that after i lifted it. new u-joint fixed it up(and shims). only did it between 45-53 weird eh?

 

[cahilc]

harmonic vibration ...

Probably harmonic vibration of the driveline. Tires will do same thing. Only act up in a specified range of mph. Weird, but interesting.

The driveline shop should spin balance the driveline too. Be sure to tell them what speed (mhp) it happens. They should be able to convert to driveline rpm and target the trouble zone.

Cheers,
Cahil

P.S. You should have nice shiny soldered weights on your driveline when they are done !

 

[saint60]

You can also check your brakes. I hade to tighten my brakes the other week and then when i went and drove it it shimmied at about 40 and up. If that is the chase all you have to do is loosen up your brakes a little. Just a thought.

 

[euclid]

Last resort if you don't find it in brakes, tires, driveshaft is the transfer. I had a similar vibration that I lived with for over a year. It was the transfer output shaft bearing. The race was so loose that when I took the back of the case off the race fell out into my hand. Rebuilt transfer solved the problem.

GT

 

[jhstatts]

euclid... did your vibration also include a rattle? I have a rattle, but no vibration. I am still trying to pin down the source of the rattle.

 

[lowtideride]

cahlic said it first but i ive been in a jetta that did the same thing.. it was unevenly worn tires

 

[euclid]

Mine was mainly a vibration, but it was bad enough that it rattled the whole truck. When I was trying to figure it out I swaped a set of tires from Jestard onto the truck and it still did it. The vibration was really hard to nail down.

Only from 45-60.
Worse when the truck was hot.
Worse right after a stop on a long trip. (my theory here is expansion\contraction of the aluminum)
Letting off of the throttle made it go away.
Flooring didn't help till after you drive through it.

If I had known it was that, I could have pulled the back of the tcase off and replaced just that bearing. Wouldn't require a full rebuild, as you can get to that bearing with just the back of the case off.

GT

 

[euclid]

jhstatts, I had a rattle that was really hard to find one time and it was the heat shield on top of the catalytic converter.

I also had a rattle when I first got the truck that was solved by replacing the bushings that hold the exaust pipe to the frame. When they go bad they sometimes get hardened.

 

[cahilc]

euclid... did your vibration also include a rattle? I have a rattle, but no vibration. I am still trying to pin down the source of the rattle.

This is going to sound real dumb, butt ...

My mechanic told me to wipe down all the door seal gaskets (front, back, sides, and hood) with a good detailing rubber conditioner. Well, gee ... truck was a bunch quieter and the rattle I couldn't identify was gone. Well ... duh.

My rear hatch was the main one but I had a rattle(actual squeak) in drivers door too.

All gone now, and mucho quieter.

Cahil

 

[jhstatts]

Cahil,

Unless my axle rebuild fixes my rattle, you'll hear it when you come by later this month. It definitely isn't the rubber, but that is a good tip. Mine is mechanical, but not coming from the engine.

 

[tradarcher]

Driveline Vibration Fix...

I HAD... the same vibration. In my searches I found out that my rear driveshaft was "out-of-phase". If you do a search on "phasing driveshaft" there are links that do a better job of explaining what phasing a driveshaft is. The attached URL is a picture of a driveshaft phased. Phasing is when the yokes are lined up looking down the driveshaft.

http://www14.inetba.com/dss/images/shaft1.jpg

 

[curdog14]

2 Words: Torque converter. At the speeds you describe and the fact that it isn't there when coasting leads me to believe that this is your culprit. I had this problem for a few years and once I replaced my tranny, transfer case and torque converter the shimmy-shake is gone.

DC
88 FJ62 w/190k
3" Lift and Fat 33's

 

[cruiserbrett]

2 Words: Torque converter. At the speeds you describe and the fact that it isn't there when coasting leads me to believe that this is your culprit. I had this problem for a few years and once I replaced my tranny, transfer case and torque converter the shimmy-shake is gone.

DC
88 FJ62 w/190k
3" Lift and Fat 33's

One word: Fixed

Driveshaft was way out of balance, so 2 new $41 Toyota u-joints and about $100 for the u-joint install and balance, and its much better. Splines on the shaft are slightly worn so I would need a new driveshaft to completely get rid of the vibration but it is nearly like new now.

As for the torque converter, why do you say that? Seems as though it would be more prevalent in a certain RPM, not only a road speed if it were the torque converter...since it is bolted to the flywheel. And I can tell you there is NO way I am going to replace t-case, auto tranny and torque converter to get rid of the remaiing vibration.

 

[curdog14]

Didn't repalce the tranny and tcase to get rid of slipping torque converter, replaced tranny (tcase thrown in for free) after too many cross continent journeys packing too much crap. Rig was diagnosed with a bad torque converter when I bought it but it would only slip between 50-55 mph. New torque converter and no more shimmy shimmy shake going down the highway. Also, I'm not the first person to diagose such signs symptoms as torque converter related.

D