2004 silverado 4 wheel drive

[TravP]

When I'm in 4 hi or auto 4 wheel drive every once in awhile my truck will start whining like its in 4 low. It doesn't make a difference if the wheels are straight or turned. I stop, put the truck back in 2 wheel drive and its fine. The differential fluids were changed 10,000 miles ago. This just started happening in the last week. Any ideas?

Thanks

[TravP]

anybody?

[Gus]

Only thing I can think of is perhaps driveline bind? Are you on dry pavement when it happens?

[NIBOWMAN]

Have your replaced any tires lately, like say just the two on the back or front. Sounds like your drive line might be binding.

[jwhjr]

I definitely get some extra noise in the driveline when I'm in 4hi or Auto, but it's more noticeble if I'm accelerating.

[TravP]

Absolutely no dry pavement. This just started happening. The noise might start one minute after putting in four wheel drive or maybe ten minutes after. I stop, put it back in 2, and its fine.

[TravP]

Its the front differential. My axle seals were leaking which made the front diff fluid low. I'll have it back tomorrow with the front differential completely rebuilt.

Total bill= $1,130 plus tax

[jwhjr]

Ouch. I had to have the passenger side front axle seal replaced because it was leaking, but luckily it was still under warranty. Seems to be a relatively common issue as I've seen other posts about it on truck forums.

[TravP]

Ya the axle seals seam to be a fairly common problem.