May be a dumb question but it will help me get peace of mind. So I’ve been looking for a set of axles with the 3.55 gears for awhile now, and finally found a good deal and jumped on a set today. They have 250k miles though. In yalls opinion Is this too much for all the work involved installing them? My jeep now has 200k miles. I plan on checking out the fluid in them tomorrow, And if I keep them I will put all new seals bearings etc in them.

 

Just check the pinion. If it is fairly tight and only has 1/8 turn or less back lash, go for it

 

The backlash felt nice and tight but here’s what I found in the front diff. The fluid also had the metallic wave when it was draining. I have a 90 day warranty I think I might be using...

the second picture is what had me worried, those were pretty big gritty metal flakes.

 

Do the pinion test on it. High pinion fronts have crush sleeves that become loose and the pinion nut backs off and the pinion becomes sloppy. Look at the gears and see if they are pitted. You might need to tighten that nut up again. Also there is a product called Power Punch for differentials which I highly recommend that will reduce wear and quiet some gear noise if you have it

 

I’m unfamiliar with the pinion test, I just checked it with a pry bar and it felt tight. The ring gear looks in good shape, the teeth on the pinion are not as smooth as I would like. What worries me is that the fluid looks like the fluid in my Dana 35 on the grand Cherokee I used to own. The gears were trashed in that thing but they looked good and passed all the tests.

overall I probably gonna take them back, I don’t think it’s worth installing them. Real good guys at the junkyard I got em at, they won’t give me a hard time.

 

The high pinion Dana 30 doesn't use a crush sleeve.