Author Topic: Differential Noises Front and Back  (Read 1419 times)

Offline Jon87V20

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Differential Noises Front and Back
« on: May 13, 2017, 12:56:40 PM »
Hi, Fellas:

I had my '87 Suburban V20 with an NP208 out at the ocean this past week and noticed, when my front hubs are locked and the TC is in 2H, the front tires are trying to stay locked together some of the time. Also, after going from 4H back to 2H with the hubs locked, when I went back on to the pavement, I took a turn and the tires seemed to be fighting each other and then we heard a loud bang from the front differential and then they were able to spin freely again.

I'm assuming it shouldn't be locking up when you're in 2H, or is that incorrect? I'm going to check the fluid as soon as possible, but I'm going to be on the road away from home for awhile and might not be able to check it out for a bit.

I also wanted to note that there's been a lot of drivetrain noise with this truck since I first bought it about 2 or 3 years ago. It slams pretty hard like there's a lot of slop in the rear diff when shifting between reverse and drive for example.

When I'm driving, there's a fairly loud howling and whining when cruising with light throttle, only while maintaining speed. The noise goes away when decelerating or accelerating.

The odometer is showing about 80,000. So I don't know if that's 180K or 280K.

Am I looking at rebuilds on the front and the rear here?

What does that typically cost (ballpark) for those of you that have had a rebuild done?

Thanks!
« Last Edit: May 13, 2017, 08:54:50 PM by Jon87V20 »
1987 Chevrolet Suburban V20 Silverado
350ci TBI TH400 NP208