Rear Axle Noise ?

[arcticcat]

Hi all i have a 1988 gmc 1/2 ton with a 305 and an automatic trans, yesterday i was pulling a trailer when i went to goup hill and it downshifted i heard a noise coming from the back that sounded like when their is a broken motor mount and the fan hits metal i can only get it to do it if it is under a heavy load or if i break torque it , under normal driving conditions no noise, i have never heard a noise like this from a axle any ideas?

[cerbomark]

I just throw this out to you, I first thought of engine knock when I read this but if you are sure it s from the rear could it be something on your trailer? Welcome!

[arcticcat]

I just throw this out to you, I first thought of engine knock when I read this but if you are sure it s from the rear could it be something on your trailer? Welcome!

Thanks,, yea i thougt of that to,, i started to think maybe the muffler or cat converter may have a loose baffle in it ,, i never heard a noise like that from a rear axle,, and i have broken many axles in my past younger and crazier days.

[levi2009]

I just throw this out to you, I first thought of engine knock when I read this but if you are sure it s from the rear could it be something on your trailer? Welcome!

 

 

A dry U joint will tick like you describe, its worth checking..........

[masterfoxscout]

Do you have a locker or a posi in the axle?