Deiveshaft/rear end clunk

[Squatting Dog]

Since its been in the mid 70s, I have been driving with windows down. I have noticed when shifting from park to drive a thump/clunk from drivetrain.
Trying to duplicate the noise and only happens at low (0-5mph) when hammering the throttle. At speed (above 5mph) I do not hear or feel anything. As far as shifting it only does it from park to drive. And not drive to park or reverse.
I was thought that they had fixed this issue...

-Greg

 

[Hocker52]

Were you on any type of incline or up against a curb? Mine does this also but it seems to be cause Im against a curb or on an incline and it puts the tranny in a bit of bind.

 

[Squatting Dog]

In the parking lot there is a slight incline, just enough to cause truck to roll back when in park.

-Greg

 

[Hocker52]

Thats probably whats doing it then.

---------- Post added at 04:29 PM ---------- Previous post was at 04:28 PM ----------

I dont think its hurting it, but I not 100% sure.

 

[Squatting Dog]

Im am just going to flog the crap out of it in Texas, and go from there!

-Greg

 

[chapba]

im glad im not the only one hearing this. low speeds and hard shifts at higher speeds are also a bit clunky for me. i always assumed it was the wonky trans

 

[Squatting Dog]

I was thinking the same thing at first, and thought it might be tuner. So I tried all three tunes and stock and it is still there. Granted I will say 5star tune does make a difference in sloppiness of transmission..

-Greg

 

[chapba]

wow, good to hear the tuner helps some!

 

[Squatting Dog]

Yes, I was really impressed.. It gets rid of the hesitation/second guessing/hunting the transmission does normally. It is not perfect, but it doesnt feel like case is filled with 50 weight oil anymore...

-Greg

 

[X_TACOMA_GUY]

The clunk is most likely in the rear axle. There has to be a certain amount of backlash in the ring and pinion gears. Backlash is a specified amount of "slop" between the gears as they mesh. If your truck is parked at a slight rearward incline, the ring and pinion are holding the weight of the truck on one side of the gears teeth. Same goes when going in reverse. The shift to drive puts the load on the other side of the gear teeth. This sudden change of load direction actually causes the gears teeth to bang into each other, causing a clunking noise.

Try this:
Set your parking brake, and put the truck into neutral. Then crawl under the rear of the truck, and grab hold of the driveshaft. You should be able to turn the driveshaft by hand back and fourth a little bit.
Its because of the backlash in the ring and pinion that you can do this. If there were no backlash, the gears would eat themselves when the differential gets warm, and parts begin to expand.

I hope you guys find this helpful.