vibration need some advice.

[duckhunter38671]

I need some help..I have an 87 4x4 22re with an a340h transmission.  It is completly stock except for the engine, which is newly rebuilt with a 261c cam and street/rv head.  my problem is that i get a vibration/jerking after you get up to speed and start letting off the accelerator.  if you let completly off there is no problem.  anybody have any ideas?

[79coyotefrg]

sounds like a u-joint about to go,    set your ebrake and put tranny in neutral  get under there and wiggle that drive shaft, i bet the joint behind the tcase is sloppy

[duckhunter38671]

I'll check that out, I did hear it make a clunk the other day.

[79coyotefrg]

yep  thats it

where are you located???
and to Marlincrawler

[duckhunter38671]

located in southaven, mississippi.  i will check the joint tomorrow, sure hope that is it and not something in the tranny.  i have heard that rebuilding that one is really expensive.

[brainlessfool]

Mississippi?    I hear good things about the dunk hunting down there! 

[79coyotefrg]

yea  but dont go huntin with brainless   ,  unless you were a bullet proof hat

[Duffil]

yea but dont go huntin with brainless , unless you were a bullet proof hat

 

[79coyotefrg]

no really   last duck season he was swinging for a shot and blasted his buddy,   didnt hit anything vital      

hey man your practicaly a neighbor

[Duffil]

yah... i read the post..shot his buddy in the head...gonna be his best man too!! best part about it!!

[79coyotefrg]

no  the best part was "didnt hit anything vital"   

[Weldo]

A vibration at speed might be caused by a warped brake rotor or a wheel out of balance.

[duckhunter38671]

well, I have been on vacation and haven't had any excessive time to be on the net, but I think my problem is actually timeing.  I have noticed if you are going at a slow speed, not giving it much fuel, it stumbles a little bit.  as long as you are accelarating you don't notice it.  anybody got any other thoughts?

[79coyotefrg]

well what year is your truck??   how are your plugs an wires??   put your timing mark on zero and pull the valve cover and check your cam timing.    it should be about 3 minutes to 12 oclock ie  just maybe 1 tooth to the left of straight up, or straight up

[duckhunter38671]

truck is an 87.  the wires and plugs were replaced 5000 miles ago, but had to go back in after the head gasket blew about  400 miles ago.  i didnot replace the plugs, which i guess could be a problem because of the water, but i did look at them and they looked fine when i put them in the new head.  on the timing , my mechanic and i have played with the timing to try to get the most hp out of the engine, which may be my problem. we haven't had time to check it out.

[79coyotefrg]

have him do a compression check,   does it seem like a engine miss?

[duckhunter38671]

not really, it just studdars.  as long as you are giving it plenty of fuel, you don't notice anything.

[79coyotefrg]

not really, it just studdars. as long as you are giving it plenty of fuel, you don't notice anything.

i would check your airflow sensor and injectors