73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: BackCountry on April 16, 2014, 07:48:45 pm
-
truck running really rough from 45-50mph. doesn't do it before or after and doesn't feel alignment or tire related. Someone suggested torque converter. does this sound right? any other ideas? At this point 100 is a lot to spend if I'm wrong :-\
1985 k10 with a 305
thanks all
-
All the u-joints good?
-
Did it start all of a sudden? Any possibility you threw a wheel weight? Does it change any with brake application? Does the vibration quit if you shift the transmission into neutral and let the engine idle down at 45 - 50 MPH?
-
not sure about the U-joints but it didn't start all of a sudden, it's been like that since i got the truck about a month and a half ago. I'll check the shift into N and brake application tonight when I get home. (wife uses it to take the kids to school during the day, my commute's too long for a gas guzzler ;D )
And I don't think it's wheel related. I've felt/dealt with that shimmy before and this just doesn't feel like that, but as usual I could be wrong.
-
As what BD said, it also could be the front rotor's, I have a expedition that did the same thing between 45 - 50 mph only. Could not fix it until I changed out the rotors. The front rotors had warped and for some reason it only had the vibration between those speeds.
-
good to know. I'll definitely check it out. cause it wouldn't suprise me. but nothing with this truck would at this point lol
-
when you say rough do you mean a mis or vibration
-
honestly, it doesn't feel like a 'miss'. but it doesn't feel like vibration either, at least not vibration from tires, but it's very jerky. I guess that's the best way I can describe it.
-
A frozen u-joint will do that. Add a load in the bed to make the truck squat a bit and see if the vibration goes away.
-
ok, so I've noticed a couple of things. first, applying the brakes doesn't stop it and it doesn't happen in drive, only overdrive.
-
Do you feel it in the steering? What's the RPM range of the engine when you feel the 'roughness' at 45-50 MPH? Can you duplicate the roughness in other gears at similar engine RPM?
-
I feel it all over, it's pretty forceful. like someone grabbing you by the shoulders and shaking lol. but I had it up to 55 in drive and it didn't do it at all. rpm's are hard to say as I don't have a tach, just an ear and it's an auto