Vibration in second gear under 2500 RPM

Lately I’ve been noticing the whole dash rattles when I shift from 1st to 2nd (R150f) until I get to 2500 RPM, when the vibrations smooth out.

I also get a clunking/lurching sensation when getting on to and off of the throttle /clutch.

Any ideas of the cause(s) of the above symptoms, and whether they’re related?

 

Far from an expert and just throwing out ideas, but sounds like it could be misfiring. That leads me to think about air, fuel, and ignition. Are you throwing any codes? How do your spark plugs look? Clean air filters?

Happy New Year! And sorry if you've already checked all this.

 

No codes. Plugs are pretty new. Just replaced my air filter. I do also have an intermittent high idle though.

 

Hmm, maybe MAF/IAF? Could explain the high idle. Feels like that would throw a code, though...

 

Have you check you engine and transmission mounts for excess play?

 

Yea it could also be a dirty throttle body. I’m not sure if that’d cause the other symptoms though.

 

I haven’t. Is there a way to check them with the truck stationary?

 

Get under there with a pry bar. Pry each engine mount and The transmission mount to see if the rubber is separating from the mount.

 

Could it be a loose CV joint causing the vibrations also?

 

If you mean that the Birfield joint itself is worn, that’s possible but would be very unlikely. That’s an easy check, grab the cv joint and check for play.