I know this is probably a stupid question and I probably over-thought it already. But here it goes anyways. I'm about to pull the backing plate off to access the bearings for the rear axle, and I was wondering if I need to or should drain the differential first?

Forgive and correct misused terminology. I hate sounding like an idiot. I have lots of mechanical know how and experience. But I'm not too often discussing automotive work. So I might have names swapped around etc.


My thoughts were that I might not need to as the oil level wont be much higher if at all over where the bearings would be at or the oil seal. I was always under the impression that something in the diff whether the gears themselves or something else specifically designed to spread/distribute/splash oil throughout the assembly.

My other thought was that if I do have some drainage once pulling off the backing plate, would be so trivial I just top everything off when I'm done.

Does anybody have experience doing this either way?


Thanks.

 

Yes you should drain it or you will have a mess.

:wabbit2:

 

Thank you. I will go pick up another container right now.

 

I'd also suggest pulling the fill plug first for a couple reasons...

First, you'll need it off to refill the diff and you don't want to find out it's stuck or round it off while your diff is empty. Second, the flow of oil out the drain will be much smoother with the fill plug out.

 

That's good advice.


My primary reason for wanting to avoid draining it was hat I just changed the diff oil.

Now I'm just trying to figure out how to seperate the shaft from the backing plate. I've been going at the "raise above your head and slam at 2x4 on concrete" method for a while now and it hasn't budged.

Don't have any sort of press access right now. Or I would just make something to bolt to backing plate.

Wondering if I could use hammer on the end while the backing plate is held between two boards resting on the edges of my brake shoes. Rotating obviously as I went.

 

I am at the same point you are. I tried the brute force method twice and I don't know how people do it without the axle hitting them in the face or dropping the whole thing. I found someone on craigslist and bought a 20ton press. I am trying to justify it by putting it to other uses.

Where are you located? Maybe someone in the area has what you need and is willing to help. Once I get my tool done anyone is welcome to use it if they want to drive to Madison, WI. Assuming my second version of the tool doesn't break.

 

That's funny, I was just in Madison about a month ago believe it or not. First Oshkosh then a concert in Madison.

I'm on the other side of the lake otherwise I like the idea.

I actually have access to a hydraulic and an arbor press. Except the hydraulic doesn't have the shut height I need, the arbor would be no way of making a tool to fit this thing (its a POS)


I also have access to a 400 Blow press that has the shut height I would need, but not only is that like going after a rat with a 25mm GAU-12 canon, the setup time would take hours, and if it bound up/didn't come out the press would keep going.

 

OK update. Using the drop from ridiculously high height onto board finally worked. I decided to try a piece of laminated plywood instead of a 2x6. One because the 2x6 I had was deforming like mad. Second the ply was thinner. Goal was to try and get a bit more energy transfer. Luckily it worked.

Now I just need to find a new bearing and axle seals as they were leaking, thus causing my suspicion of the bearing being the cause of my drive line vibration.

However now that I'm looking at it...I pulled the rubber covers off of the bearings and things don't look to bad. I was always under the impression that with bearings like these any play means its bad. Does anybody know how much is acceptable? I'm replacing it anyways but should I search for other sources of vibration if it might not be the bearing.