Welding Armor to Differential - Seals?

Hi all. I'm in the process of fabricating some differential armor for my truck after a nasty encounter with a rock, but am torn between welding it on or bolting it on (or welding mounts to the diff and bolting it to the mounts - ideal). My main concern here is welding to the differential and destroying seals or otherwise. Has anyone else had experience doing this? What are your recommendations? I realize there are a ton of companies that offer weld-on armor but I don't know whether this is usually done with the third member and all seals removed. Thanks in advance!

 

Pull the differential out if your welding on the axle housing

It is a pain but better then needing to buy a new one

Unless you really control the heat and allow things to cool between the stitch welds

I learned this lesson the hard way the first time

 

The diff itself is cast. Welding cast is a big no no. Cast is dirty, meaning the weld will never be strong due to all the impurities in it.
Your better off welding on the axle tubes than the diff. Can you weld without gutting the diff? Sure. Just control the amount of heat.

 

weld up some armor to the cover. i wouldnt weld anything to the actual third (i think its actually forged and not cast)
also, you arnt doing a bunch of welding, just do a few 1" welds and call it a day. you dont need to pull the third.
I did this on mine.

 

Hi all. Thanks for your replies. I had no intention of welding to the diff housing itself, rather only on the axle. I welded a small bracket to the bottom of the axle and I could touch it within minutes of welding it on so I'm really not too concerned about having done any damage ("perks" of an unheated garage....). Success! Thanks!

 

She ain't pretty but neither is axle damage! Note that those bolts will soon be countersunk, and the back will be made taller to provide more protection to the back of the axle! Also, excuse the gross welds on the bracket.. welding underneath the truck often proves tricky without a lift.

 

looks good to me!!!

 

Thanks man! The welds on the actual plate are kind-of a funny story... I had been in the garage for a long time and was getting really tired and when I switched from 4042 Al filler to steel filler I put stainless in by accident... thinking it was mild I was really confused why the welds weren't flowing well and oxidizing immediately. Oops... Needless to say when putting ER70S6 (mild) in they looked a little better lol. Should still hold though.