Mr.Utah

Hey, I have a 87' truck 22r carbed, manual. I bought this thing in January and have done tons of work to it. One thing I can't quite figure out is that it likes to jerk back and forth when on highway, with little or no load on the motor. As your maintaining speed on the freeway and just very slightly accelerate, the truck kind of bucks a little. If I give it a lot of power, this does not happen. I have searched many many threads on this.

Timing is correct on new motor.
New rotor, cap, oe toyota wires($80), coil.

Could this possibly be the distributor itself, fuel pump, or something else?

I dont know, let me know what you think?

Janderson31R

I don't know if we are having the same problem or not but it sounds like it. I thought it was my drive shaft so I worked that over and it didn't fix it. I took my truck over to a buddy that works in a 4x4 shop and he told me it sounded like the bushings on my front end were toast. He wasn't too specific so I just ordered a master bushing kit for the entire truck. When I crawled under there to replace them none of them seemed too bad but there was a little play in a few of them. I decided it was a lot of little things working against me. The only bushings I didn't replace yet are the tie rods because they were the only ones that didn't come in the kit. It seems to have fixed the problem though I haven't driven a whole lot since replacing everything. Don't know if it will help just thought I would throw it out there.

Mr.Utah

I would not have expected bushings. I r&r transmission, same mystery bucking and jerking. Mine only seems to happen when slightly accelerating after maintaining speed. There is no problem when accelerating quickly.

Thanks for the bushing tip, let me know if it works for you in the long run?

Mr.Utah

Oh, where did you buy your bushing kit from?

Janderson31R

I got it from a local place called safari ltd but they just ordered it from energy suspension. The only other thing I did was replace the stock carb. I don't know exactly what its called but that little rubber boot on the left side kept tearing and I got tired of rebuilding it so I got a webber. Im not sure if it was the carb or the bushings but the truck runs smooth now. I have two stock carbs sitting in my garage one was rebuilt a little bit ago and the other one needs rebuilt. I threw the one away that I rebuilt four times. If you want one of the other carbs I will send it to you just pay shipping and its yours. They want way to much for them online. If you want I will get you a part number for that bushing kit also.

ct_tuckrunner

Could be similir to my problem. I feel the same thing because my rear end is blown. Can you hear the rear making a lot of noise? Get under it and grab your driveshaft near the rear end and see if there is a lot of play there. I think 1/8" is what is considered tolerable. If you have 1/2" like me, you're screwed!

Mr.Utah

I'll check the rear end, and YES, I'll take the carb and give it a try, How do I pay you for shipping? Oh, and I'll take the part number as well for the bushing kit. Thanks janderson

Janderson31R

If you have paypal we can do it that way. The rebuilt carb hasn't been on a motor in a while but it was good when we pulled it so ill send you that one. Send me a pm with your shipping info and I will get a price to ship it and we will go from there. I have an 83 so the part numbers might be different but it will give you a starting point. If you know anyone that wants that other carb Ill give them the same deal just pay shipping and its theirs. Ill get them cleaned up this evening.

Mr.Utah

ok jusst pm you janderson

Mr.Utah

bump......anyone else with this problem

peow130

I used to have this problem.
Then i noticed a bunch of my vac lines got removed/fell off.
Put em back on, and problem solved.

Mr.Utah

I think I figured it out! !! At the suggestion of CT tuckrunner, I was checking the rear differential and driveshaft. I did not know if I should be checking rotational excess play or up and down slop of the driveshaft. Anyway, I changed the rear diff lube oil....NO change, still clunky at slight throttle or slightly coming off the gas while cruising.

THEN I thought maybe I should lube the zerks in the drive shaft, lubed then up and it took a lot of grease? Hmmmm, so I took her for a test drive and I could not duplicate the jerking/bucking/popping/clunking as usual.
Wow, I cant believe that a lack of grease was causing the problem. I was getting ready to replace fuel pump, whole distributor, etc..

S0...GREASE YOUR DRIVE TRAIN, it will feel much better.

T_F_E

^ thanks a bunch I had the same problem but Ive been ignoring it. Little grease goes a long ways!