Rear Diff Cover Magnet Question

DSN46 · August 11, 2008

I have recently been reading threads about rear diff maintainance, etc. I came across one that discussed the magnet inside.

I serviced my rear diff last week (drain, clean, refill). The magnet came off in my hands of course, and I thought it was like all others in that it was just stuck in there by magnetic force. Then I noticed the glue on the back of it. Well I used RTV Black to stick it back on and let that setup before putting the cover back on the diff. Do I need to worry about it coming off now? I didn't think that diff fluid would break down and dissolve the RTV and let the magnet float around, but then others are saying that you should use "Gorrilla Glue" or something.

So... should I worrly about it? And if it does come off (since it a flexible material) will it just get chewed up and not hurt anything? OR.. do I need to go and take it all back apart, drain it again, and use the glue intstead?

Any thoughts are certainly appreciated!

Thank you for your time.

James

mipsco1 · August 11, 2008

i would say that it will most likely hold fine and you sould have no prob. but, if your anything like me every time you drive your truck you will be picturing that magnet come off and chewing the crap out of your rear end. if it was me i would drain it, use a glue that made for applications like this(prob have fun finding on) and refill it again. All it will cost you is a new $8 gasket.

DSN46 · August 12, 2008

Thank you for the reply!

You are right... all I can think about while headed down the road.... "the magnet.... getting chewed up back there.... pieces clogging my axle tubes and ruining my bearings..."

I can't get to it right away.. but I see another drain.. re-glue.. and refill in the near future. I just hope it holds out until then.

Any idea at all about where to get the right "glue" for that application?

James

peteking · August 12, 2008

I've heard about the Gorrilla Glue method. I have not performed this process but it makes the most sense. Silicon adhesive should stand up to the gear lube just fine, but I can't imagine that it's a long term solution. Gorrilla glue is strong stuff and should last longer...IMHO.

Dyabolical · August 12, 2008

If the magnet does come off, it is just a ceramic material and will crush alot easier then the hardened steel that the gears are made of.

Also, the magnet SHOULD sink to the bottom of the housing if it was to become dislodged.

remington351 · August 12, 2008

I had the exact same question so I emailed PermaTex. They said RTV is not recommended for "continuous immersion" and will loose its adhesion after a while. The tech that responded said their high strength epoxy's are appropriate for this application. Hope this helps.

DSN46 · August 12, 2008

Thannnnk You!!

I feel better now. Not in the "Hey I can forget about this now" kind of way, but the "at least it will hold another couple of weeks until I can service it again" kind of way.

I appreciate the guidance on this guys. I will start searching hardware and auto parts stores for the ultimate epoxy.

I cant thank you enough.

James

Zembonez · August 12, 2008

Even if it did dislodge, the rear axle grease is just circulated by the ring gear picking it up... not quite like having a high volume pump. The magnet should drop to the bottom. I bet it would never get kicked up into the gears.

pennzoil29 · August 12, 2008

Even if it did dislodge, the rear axle grease is just circulated by the ring gear picking it up... not quite like having a high volume pump. The magnet should drop to the bottom. I bet it would never get kicked up into the gears.

I'm going to agree with Jim on this one. I also think it was mentioned in another reply.