06 Manual Transmission Slap
 

OK well when i bought my truck in november i had this faint noise coming from my transmission when i was shifting from 1st-2nd and 2nd-3rd i wasnt too bad but i took it to the dealer and they had to replace my slip yoke. they said my u-bolts were fine and also that with the 4x4 w/ manual transmissions they have been known to make a slap. i was trying to find out if its a certain make of transmission, my transfer case, or how i drive because the noise isnt getting any better. any help?

My truck makes a slap sound when I change gears. I think there is too much backlash in the rear end.

did u take it to a dealer or anything?

No. I'm way out of warranty.

It also does it when I'm in gear and I let go of the gas for a bit and step on it again.

Yeah, it sounds like a backlash issue in the rearend, or a U-joint going bad.

fddriver02, have you checked your motor mounts to ensure one isnt broken?

Yeah. Motor mounts and tranny mount is good. U joints are also good. I can however spine the driveshaft by hand a little. I am almost certain the rear diff has too much backlash. I know for a fact that the front diff is gone but I'm guessing that is Ford's fault for not torquing the pinion nut properly. I can't do anything about it since noticed that the noise was in fact my front diff and not my ball joints was about 8 months after Ford had worked on it. No worries though since I have another front diff at home and I will just swap out the rear diff for an Exploder one.