Low Speed Growl?

[wcjp]

I developed a low speed growl/rumble on my 06' Mega. Below 15mph it feels like I'm driving on Super Swampers. I normally have 19. 5's on the truck. I swapped the stock tires back on. No difference. I also just put on a new passenger side unit bearing. Swapped the stock unit bearing back on to the truck. No difference. Also pulled the front driveshaft. Still rumbling at low speed. Pulled front/rear diff plugs. No metal. Gear oil looked great. Had my wife drive the truck past me at low speed in a parking lot. Nothing obvious from outside the vehicle. I've had the steering box brace for 2-3yrs. Rear driveline looks ok. Front axle shaft Ujoints also look ok.



Can bad shocks cause a growl/rumble? Can the steering linkage cause a problem at low speed only?

 

[jelag]

Is the growl there just under load or all the time... . if its just under load its most likely u-joints... I run 19. 5" on my stuff and have not had a problem with any noise except for the noise you hear when a joint goes bad under load...

 

[MMeier]

I'm with Jim on this one... . U-joints ! BTDT !

 

[bighammer]

Drive it for a bit and find a clean, level place to crawl under. Feel all the U joint caps and see if there's one that's much warmer than the rest.

 

[wcjp]

Drive it for a bit and find a clean, level place to crawl under. Feel all the U joint caps and see if there's one that's much warmer than the rest.

I'll check the rear driveline Ujoints today with my infrared thermometer. Visual inspection was ok.

 

[04blackcherry]

Funny, I was just about to start a new thread on u joints. My 04 was good under power but shook bad at low speed when I let off and got worse until full stop. It was like I was driving on railroad ties. Once I was back up to speed everything felt normal. It was a frozen cap in the center u joint on the 2 piece rear driveline. The u joint in question was just a little warmer than the others. Visually there was no difference and there was no play that I could detect after getting it home and taking all the tension off the driveline. I didn't find the bad joint until the driveline was removed and the joint wouldn't move in one direction.

 

[wcjp]

Thanks guys. The center Ujoint was 98° when I arrived at work. The TC and rear axle Ujoint were 78°. Think I'll replace all three. Probably replace all three on the front too. One of them felt notchy.

 

[Bernie]

I developed a low speed growl/rumble on my 06' Mega. Below 15mph it feels like I'm driving on Super Swampers. I normally have 19. 5's on the truck. I swapped the stock tires back on. No difference. I also just put on a new passenger side unit bearing. Swapped the stock unit bearing back on to the truck. No difference. Also pulled the front driveshaft. Still rumbling at low speed. Pulled front/rear diff plugs. No metal. Gear oil looked great. Had my wife drive the truck past me at low speed in a parking lot. Nothing obvious from outside the vehicle. I've had the steering box brace for 2-3yrs. Rear driveline looks ok. Front axle shaft Ujoints also look ok.



Can bad shocks cause a growl/rumble? Can the steering linkage cause a problem at low speed only?

Also, check your front wheel hub assemblies (wheel bearings). I'm not sure if that is waht you meant by unit bearing. My truck was doing the same thing and it was both the wheel bearings and the rear shaft.