What's going on with my truck ? Solved

I'll try to describe the best I can.
You know when you ride down the highway and drift off the road and hit the warning grooves they have. At about 35-40 mph SOMETIMES I'll get that same sound and feels like I'm running over those grooves. If I maintain the gas when it starts it will continue. If I let off the gas and go back in it, its gone. It doesn't do it all the time, just sometimes but I have noticed it does it in the same place on my drive home which is a slightly up hill stretch of road but I have noticed it in other places as well.
I've got no vibration driving down the road and only notice it at low speed when truck has a little resistance (slight up hill).

Any ideas ?

Just FYI, I just put a transmission in it about 3K miles ago but it runs and shifts fine. My mechanic sold his business so I'm going to have to take it to a new guy and I just want to have an idea before I take it in there so I don't get taken for a ride $$$$

Thanks guys

 

torque converter shudder maybe?

Are you lifted? are you 4x4?

 

Does it go away when in 4 wheel drive?

 

That replaced tranny will cause someone to really scratch there head, I’m sure.

 

I would start at the trany because of recent service. A good check over of fluids even take it to a trany shop for a free road test. Under load can point to other areas CV axles, wheel bearings, u-joints and rear end. Ask your friends others in your area about a mechanic that's trusted.

But the no vibration or odd feeling is puzzling because it's load related.

I'm sure someone else will chime in because they may have had same problem.

All the best

 

Make sure your tranny fluid is topped off is definitely first. Sounds to me like what people experience with the torque converter, but is sometimes alleviated with correct fluid level. From your description it seems unlikely it would be the wheel bearings. I'm guessing it's auto, so try shifting it from D to 4 when the shudder is happening and if it goes away instantly I would suspect it's not a bearing problem.

 

For piece of mind, I would get the tires rotated and balanced. Have the tire shop check for play for the wheel bearings along while the truck is off the ground. I would rule WBs out especially if you are still on the original WBs.

 

Well, you guys are right. Right after I posted this I called my guy who built my transmission to ask him for a mechanic referral (he only does trans) and told him the problem. He said "I know exactly what that is, bring it back to me, your torque converter is chattering."

Said he was going to put some "Friction Fluid" in it and to give it 20 miles. If it still did it after that, he was going to have to replace the torque converter.

Thanks guys !!

 

Double check the driveline components to ensure they are all tight. As well as checking fluid level like others have noted.
-Where the driveshaft bolts to the axle pinion flange, carrier bearing bolts and transmission mount bolts.
-Grease and inspect your U-Joints and driveshaft slip joint as well.
-Do a good once over of the transmission installation overall, bell housing bolts and such.

 

Hope if you got the trans from him he's doing you a favour here. Hope it resolves your problem and keep the thread updated!

 

Have him install a Trans-Go shift kit while he’s there

 

I'll keep ya updated. Trans came with a 25K warranty and he owns the shop. I took it to him at lunch and he got it done. I'll know something in a week or so (drive to work is only 4 miles).

 

Make sure the proper process was followed for proper trans fluid level.