Questions about 500 mile differential fluid change

Pfarmer

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Burnet, Texas
Just got done with the 500 mile break-in for Yukon Super 35 kit. (I think Yukon calls it the Ultimate 35).

Two Questions:
#1. The front, stock Dana-30 cover does not have a magnetic plug. Should it? Should I replace it with a magnetic plug? Stick a magnet on the outside somewhere?

#2. There is obviously a pretty good oil/metal slurry in the differentials from the break-in. Group A says, "You HAVE to clean all that stuff off the gears with brake cleaner." Group B says "Never put any sort of solvent in your diff. It could mess up seals, hoses, etc..." Real world experience???

Thanks for the help - Paul.
 
Spray it out, let it dry. It doesn't have to be surgery clean.
I like the magnetic plugs and use them when I can.

Nice area of TX you're in. My folks lived in Marble Falls and Buchannan Dam for a while.
 
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If it were mine I'd just do another change at say 1000 miles to flush everything out, but I don't see a big problem with using brake cleaner as long as you don't directly soak the seals. Lightly spraying off the gears and using a plastic spoon or something to scoop out the remaining fluid in the bottom shouldn't cause any issues.
 
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Spray it out, let it dry. It doesn't have to be surgery clean.
I like the magnetic plugs and use them when I can.

Nice area of TX you're in. My folks lived in Marble Falls and Buchannan Dam for a while.
I’m looking for a magnetic plug. We certainly love this area of Texas.
 
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Jerry, they were filled with conventional when the new gears were installed. You’re saying to go back with conventional again??
You have a good shop since they knew to use conventional gear lube. Yes I'd only use conventional for your 500 mile change too. The R&P gears run a lot cooler when lubricated with a conventional gear lube and heat is the enemy of gears during the break-in process when they run hotter. Conventional 'sinks' the heat out far better than a synthetic does.

Since learning that from John Currie I have run nothing but conventional gear lubes even after gear break-ins. I was talked into running synthetic during my last break-in and the rear gears got too hot and failed. The gear guru I took my Jeep to to change the gears took one look at my gears after he got them out and said emphatically 'you used synthetic gear lube didn't you!' He said it was clear the gears had gotten overheated during the break-in and added that the setup pattern looked fine. He filled the case up with conventional when he was done and said to avoid synthetic for anything except factory installed gears that come pre-broken in (pre-lapped). He added he won't run synthetic even in them if the vehicle is used in hard conditions.
 
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