vibration driving me nuts

[tofargone]

I am about a day away from lighting a match and watching the damn thing burn. I have a 98 hoe with 140K. I bought it with 136K about 3 months ago. When I bought it I had a bad shake when holding a speed between 45 and 60 going up a steep hill. I also threw a code for a random misfire. So, changed the plugs, the cap and rotor, the coil. Had to tighten up the exhaust cause of missing a gasket at the connection. New U joints, new shocks, changed all fluids, greased everything up. now I throw a code of #4 cylinder. Took it to a mechanic friend of mine to go over, front end was solid. Tranny and torque converter don't seem to be the problem. The vibration feels like the motor is trying to jump out of the truck and some times it does throw a code. I am going to run the seafoam this weekend to see if cleans it out, but any ideas would be appreciated.

Thanks

 

[qlc1964]

check the motor mounts &trans mount

 

[97cleantahoe]

are the tires balanced. seems stupid I know, but my friend had a shaking prob and spent alot of money trying to fix I said check the tires he did and got them fixed and it stopped.

 

[96ProCompTahoe]

i have to second the motor and trans mounts

 

[metro273]

Hmmm, seems odd?

 

[tofargone]

I checked the mounts and they are all tight and not cracked, and the tires are new, I had the tech look over the rims prior ( it did it before new tires) and he said they were fine.

I just seafoamed it yesterday ( man was that cool ) and put new plug wires on also. I didn't have the vibration after that, but it seems to be somewhat intermittent so I will have to see if it comes back. I will post what I find in the next couple of days.

Thanks for the advice.

 

[bsamoul]

what steps did you do to seafoam?

 

[tofargone]

Put 1/3 through the brake booster vacume line and the rest in the gas tank. Also changed the plug wires and the vibration has been gone for the last three days. I'll give it a couple of weeks before I celebrate, but I'm crossing my fingers its licked. Next step is to clean the throttle body and intake. I have some major carbon buildup in the throttle body.

Anybody know best way to clean these out.

Thanks