My front differential has a very weak magnetic fill plug. The rear has no magnets at all.

I want to put some neodymium magnets in the bottom, but those things can lose their magnetism at relatively low temperatures.

Best I can find are some old tests saying that differentials in general should be ok with intermittent temps of 300ºF. Since I don't want to add anything that will be the new weakest point, I'll start with an assumed max temp of 350ºF.

Anyone have some data that would help safely lower that, or that shows that to be too low?

As far as the worst-case operation conditions... Off-roading happens, but on the mellower side. On the roads, worst would be towing ~5,000 lbs up a pretty good incline on a 100ºF+ day.

Thanks!

 

Bought 50 of these. Only 300ºF limit, but I figure there are plenty of other good uses for them if it turns out they won't work.
http://appliedmagnets.com/high-temp-...ock-p-909.html

Next time I open up the engine/transmission/transfer case pans, I'm planning on putting one of these in each:
http://www.magnet4sale.com/n35uh-2x1...il-pan-magnet/

Higher temp rating on the second one, but not quite the clearance I'd want in the diffs. I'll give them a shot if they get here before the smaller ones. Will be back with pictures.

 

You can buy aftermarket differential covers that have a drain plug in addition to the fill plug. I drain mine often as its in deep water often and I inspect the oil for any metal in the pan, if there are any pull the cover and inspect. I still pull them 2 times a year just to inspect gears and lockers.