I have changed the MAF sensor, the spark plugs and the wires, and balanced the wheels. It used to vibrate a lot more and excessively at >65mph. Now, it drives well but vibrates at 50-55 mph and it is smooth at 60-80. I have not driven beyond 80 mph.
The passenger side (seat mainly) vibrates at all speeds. I am not sure what to do.
DOES IT VIBRATE BELOW 50 MPH?
@Rsitz656 No it does not vibrate below 50 MPH. The vehicle doesn't run smoothly - as I always feel a subtle vibration even when parked and not in gear when the engine is running.
Did you check motor mounts, air filter, injectors ... ? There can be many things. Probably there was a reason car was at auction.
The guys at the city yard probably got tired of working on it and not getting anywhere....the Supervisor shunted the truck to the TBS - to be sold listing to get it out of their hair...or whats left of it..
I have replaced the air filter. it was very dirty. this vehicle was used for construction permit inspections and it was very dirty when I got it.
I will try to learn how to check the engine mounts and the injectors.
I have had the vehicle for over 2 years and have driven it every where. It runs fine accept for the vibration at 55 - If the vehicle is running at a good rpm even that is not as noticeable. that happens when I want to get to 60 and just accelerate beyond 55.
@g-t I have noticed 2 more incidents in the past month: when in Reverse if the vehicle is stuck against a curb or something and I press the gas it shuts off. this has happened twice. Also, the vehicle hesitates to start. It is possible that the injectors are not clean or that the fuel pump is slowing down. I am trying to do all the easy stuff before touching this issue - what do you suggest?
What is the mileage? Is it automatic?
Reminds me of one truck I worked on similar like this...with two piece drive shaft....the drive shaft was not clocked properly.
NOT saying this is the cause but check anyways to be sure.....
@Dion thanks for this graphic. I crawled under the vehicle and verified that the phasing is correct.
I have noticed some dirt around the stems of the universal joint. I have recorded it with my phone when I switch to reverse, neutral and drive and it doesn't seem bad. Should I try to clean the dirt with toothbrush and see if there is something wrong with the seals?
Check u-joints also.
@oldandy - I have checked the u-joints by recording their behavior with a camera while I switch from drive to neutral to reverse and then back to neutral and to drive. I see a little bounce on the front u-joint. Please see the videos here:
https://photos.app.goo.gl/auEiLP68smLhFQxy8
I see what you mean. I would replace it and see if that helps. I read that your truck runs a bit rough. If the u joint isn't the culprit, see if you can smooth out the engine.
Check the Simple things first that can be associated with vehicle vibration at speed.
bad tire (snapped belt), dirt clumped up on wheel (will make a pickup bed nearly jump up and down at speed if it’s heavy clay caked on there). Dirt caked on to the drive shaft, bent or dented driveshaft.
(Edit I missed in original comment that you check the wheel balance already)
@mikaef great points. I checked them and cleaned those items. that did help with reducing the vibrations.
Does it vibrate below 50mph?
@rsitz656 no not really. however the vehicle doesn't run smooth at all times either. When Idling, you can still feel it while sitting inside.