Squeaking noise under load that matches wheel speed

[smallblockblazer]

Hey guys I have been doing some searches and can’t find a thread discussing the issue I’m having with my 1973 blazer 4x4. The issue is a loud cyclical squeaking noise that only happens when the drivetrain is under load (accelerating or braking) and sounds like it is in the front. The noise matches wheel speed so I believe it must be somewhere between the transfer case and the hubs. The truck has the full time 4x4 transfer case btw. If anyone has any ideas what this could be I would really appreciate your input. At this point my only idea is to remove the front driveshaft and put it in 4h lock and see if that changes anything. Thanks in advance!

 

[obijuank5]

I'd look at the axle shaft ujoints first.
Look for any powdered rust at the caps.

 

[mrk5]

Probably worth checking wheel bearings.

 

[Wes Harden]

Could also be u joints in the drive shafts. Drop the front shaft for a quick check.

 

[smallblockblazer]

Thanks for the responses! I think u-joints makes sense I’ll check that out

 

[pismorat]

I agree to check u-joints first. I've also found that a speedometer cable can do the same thing, and being right behind the gauges can either whine or squeal, making it seem like it's something deeper.