Vibration at lower rpm

[fast14]

Last night during feature I noticed a vibration at lower rpm's (on cautions), on throttle only, when I got up to full speed or just coasted it wasn't there anymore. Don't think it was front oriented because I didn't feel it in steering wheel. Just looking for a starting point as to what to check. Running Bert ballspline, new driveshaft, fresh rear. New to all this so any help would be appreciated. Thanks!

[racin6mod]

if the vibration went away maybe it was a mud clot in one of the rear wheels.I have ran into that in the past on the lr. started running a inner mud plug after that.

[jdpower]

Last night during feature I noticed a vibration at lower rpm's (on cautions), on throttle only, when I got up to full speed or just coasted it wasn't there anymore. Don't think it was front oriented because I didn't feel it in steering wheel. Just looking for a starting point as to what to check. Running Bert ballspline, new driveshaft, fresh rear. New to all this so any help would be appreciated. Thanks!

Check water pump, fan and U-joints. I had a fan out of balance last year and it was so bad the water pump bolts to the block worked loose.

[dirtslinger71]

check your ballspline also. i have had similar problems and it was that.they have a cheap rebuild kit for it.

[BIGFREAK101]

I must ask you don't have a ct525 or 602 or 604 these all need externally balanced flywheel. Also make sure the rearend is located left to rt is correct. To for out of line and you can get a vibration and check the j-bar make sure its not hitting the yoke on the rearend also just some thoughts . Good luck with it.

[vms]

I am have the same issue. It just started doing it. I changed to a shorter yoke and checked the side to side measurement.
I did notice after i got it on the track and made some laps. i got under the car and it seemed like i was able to wiggle the yoke as wear before i couldn't.
But i had the 8inch yoke and mine wasn't set up for the 8inch so i went back to a shorter one.
6 shaft on the yoke now. any ideas

[fast14]

Our problem ended up being in the ballspline trans. I bought this one used but freshened, however whoever freshened it did not tighten down nor locktite the friction bushing on the end of the splined shaft and it messed up the threads on the bushing and allowed the spline shaft to move around, no other damage upon inspection. Put a new bushing in, tightened it down good and locktited it good! No more problems! Thanks for all of the help everyone!

[vms]

can i pull the tail housing off with the tranny in the car and change the snap ring and shaft bearing? Is there a trick or simple?