When I am cruising along in town at about 60 Kph ( about 40 mph) and take my foot off he fuel there is a very distinct clunk which seems to come from the rear of the truck. I think it is probably in fourth gear but it sounds to me like it was just going to change gears when I take my foot out of it and this thunk happens. It usually happens more when the truck is cold. This doesn't seem to happen at speeds below or above the 60 Kph. It still is on warranty
(18,0000 km) but I like opinions before I take it in to the shop. My description may be odd but but I hope you get the idea Thanks

 

I though I had something like that too, but remembered I had a receiver in my hitch and was moving around a bit...

 

Update on my possible problem. Today it happened again. Just left home and going down the road at 62 Kph and light turns red so I take my foot off the peddle and there is very distinct jerk and it is loud. Sounds like the rear end is going to fall out of it. So I experiment a little bit and it seems the shift point from fourth to fifth gear is very close to 62 so I have to assume when I take my foot off the fuel that it is confusing the transmission somehow, because it wants to shift into fifth from fourth and by releasing the foot feed it doesn't know whether to go up or down. Any suggestions as to the problem. Should I be concerned or could it need a "flash" (which I don't really want to do because it is running very well otherwise). Thanks for any responses. I ask the question here because if nobody on the forum has any good suggestions then the dealer will be stumped for sure.

 

I had alot of slack on my 07 Mega Cab that i traded for my 08. It was an auto and when you came up to a stop the truck seemed to stay in 4th gear until you were almost stopped and then it would downshift to 1st really hard and bang the slack it sounded horrible. It would also bang pretty loud when you placed it into park. The dealer told me it was normal but I know it couldnt have been. I purchased the extended warranty for it just in case. It was a very loud clunk. It almost sounded like the rear end was shot or had way to much slack. Which with those trucks having the large hollow aluminum driveshaft a little bit of slack goes along ways. The aluminum driveshaft is good for nothing but amplifying noises.