JB_Pgh

I'll try the STP, thanks.

No noise coming from the diff, so I'm not overly concerned. I've changed out a half dozen gaskets & fluid on diffs in Jeeps, so I'll just do that one myself.

We've agreed to $5,000, I just need to come up with the money I'm short...quickly. Hopefully, I'll have it next week. Looking forward to participating here much more!

Thanks for all the help.

transmaster

For Gods sake don't put STP in anything you own. Have you ever torn down and engine that has had this crap used in it, what a mess. Instead get some Seafoam, or Marvel Mystery Oil and put it in your oil. It will clean up the lifters. If they still clatter replacing lifters is not a big deal, just time consuming from the number of bolts you have to remove and replace. Replace all of the lifters and the push rods and the problem is fixed.

JB_Pgh

I've heard good things about seafoam.

I'm not afraid of digging into the engine so if that doesn't work I might put lifter replacement on my to-do list.