Front End Vibe Question?

[TylerMartin]

Hello All,



Today I was coming home from a 250 mile trip and at about 30 miles left to go a strange thing happened. I let my foot off the throttle (cruising at about 65 mph) and a loud hum, that sounded like an exhaust brake, came from the front of my truck. It was odd but when I sped up it and kept continuous throttle it totally went away. When I came to a stop sign, I geared down and applied the brake to stop and sure enough the hum came back and my front end started vibrating really bad which I could feel in the transmission and the brake pedal. It practically vibrated the change out of my ash tray. When I took off from the stop sign, there was no hum or vibration. The vibration was like driving on those "wake-up strips" on the highway at low speeds. The vibration lessened and eventually stopped as I came to a stop. The vibration cannot be felt while cruising at any speed over 15 mph.



Does anyone have any insight as to what may cause this? Possibly worn brake pads, malfunctioning ABS system, or maybe a front axle joint (4x4)? I have to leave for work on monday and I want to get this fixed ASAP. I'm still able to come to a stop but not without my teeth rattling!



Thanks in advance for the help and/or suggestions!

 

[AKAMAC]

Check the u-joints. Also check the carrier bearing if you have one. A carrier bearing will do that. Does it do it only when your braking? Mike

 

[TylerMartin]

Yeah, it only seems to do it when I'm braking.

 

[JHardwick]

Once again, I'm betting the farm on rear ujoints :-laf

 

[AKAMAC]

Or warped rotors.

 

[TylerMartin]

It turned out to be two warped front rotors and worn brake pads. Could have been worse I guess.



Thanks.

 

[TylerMartin]

So I picked my truck up from the shop this afternoon. Pulled out and came to a stop at the stop sign. I couldn't believe it, it was still vibrating! I took it on the highway and sure enough it started vibrating while at cruising speed. I took it back to the shop and questioned whether or not they had completed the work. They ensured me that they had. I took it to another shop where they diagnosed the vibe as a result of worn rear u-joints. They were siezed up pretty good. I get my truck back tomorrow so now hopefully it is fixed.



For you guys that mentioned rear u-joints, you most likely were right! But I'll let you know for sure after the "road test".

 

[JHardwick]

For you guys that mentioned rear u-joints, you most likely were right! But I'll let you know for sure after the "road test".

I haven't lost the farm on this bet yet :-laf

 

[TylerMartin]

Yep, I replaced the two rear U-joints and sure enough the vibe is gone. Unfortunately, the shop tried everything they could to make the aftermarket joints ($28) fit but they couldn't make them work. Therefore, I had to give in and buy the Chrysler (non-greasable) joints at $191 each!



At least my teeth aren't chattering anymore.