Differential Plate Screws

[Badass69]

You all made some excellent points and suggestions that I didn't think of. I am definitely going to try soaking the bolts in some kind of solvent and cleaning out the holes with an air gun best I can and just re-use the bolts. I only wonder if I had a GM dealership do my differential, would they have went "by the book" and replaced those bolts with brand new ones? I am guessing they would NOT, but I could be wrong...

 

I appreciate you all for your advice! Oftentimes just hearing what other folks are doing or "would" do in certain situations helps a lot... especially for a novice DIY'er like myself.

 

Thank You!

George

Back when I worked for someone else and had a company truck I would get the local gm dealer to change oil in the diffs. The bolts were the original usually rusty ones the truck had when it entered the shop. And no they didn't charge for fastner replacements either. Good plan and good luck!

[Rocko973]

Thank you. Well, I called the GM dealership today to check into some belts, and I asked about the differential plate bolts just out of curiousity, and here's what I got:

 

1) They cost about $5.50 for one bolt, and they don't even stock them.

2) The guy I talked to sounded incredulous that I would even think about replacing all the perfectly good bolts with brand new ones.

3) He said to NOT put anything on the bolts such as thread locker. He was surprised when I told that my original ones had something on them.

 

When I told him that they go in tight, his recommendation was right along the lines of all your suggestions- said to clean bolts with something like WD-40, and maybe spray some brake cleaner in the holes to clean them out. He said their techs would always re-use the bolts, unless they were broken or something.

 

So much for the Service Manual! So you guys were right on!

 

Thank You!!

[CapitalTruck]

I did the exact same thing as you. Based on my shop manual I went looking for the bolts. Like you, they looked at me like I was crazy and yes, they didn't even stock them. I think the manual says to change them because they can get to rusting and the heads become distorted (might not be able to get them off next time). Having said that, I have taken my diff. cover off twice over the course of 180k miles and haven't have a problem. Mine had some stuff on them too. I didn't clean it off. I just stuck them back in and tightened them (gently) down. As an aside, I couldn't believe the amount of trash on the magnet when I changed my supposedly "never needs changed" diff fluid at 75k miles. After the second 75k I had almost nothing on it. I guess just manufacturing leavin's? I'm glad I changed that "permanent" fluid.

[Rocko973]

Just a quick update: I just did my diff fluid change, and I re-used the bolts. To get the old stuff off the threads, I just soaked them in acetone, then scrubbed them with a wire brush. For bolts with a lot of stuff on the threads, I used a pick, like a dentist, and picked them out. They all went back in pretty clean and smooth. I also put a tad of blue medium strength thread locker, the one that says "service removeable", on the threads when I put them back in. You might think I am crazy, but I also marked the bolts so that they go back in the same hole they came out. Also, I used some cheap gasket maker, just a dab, to hold the paper gasket in place while I put the plate back on. I used RED LINE gear oil, 75W 90 NS (without the limited slip additive), just under 3 qts. That's how I did it, and everything seemed to have gone pretty smooth...