Does anyone know where i can find a write up for Muncie 4 Bearing replacement? Axle shafts have a lot of play and I would like to replace the bearings myself but would feel better if I had somewhat of a guide to go off of or at least some pictures before I open it up and I can't find anything on the forum or youtube. Would appreciate any info or advice. Thanks, Brendan.
------------------ "America is all about speed, hot nasty bad-ass speed" - Eleanor Roosevelt
You can weld the inside of the bearing races that are pressed into the case. With the weld shrinkage, the races can almost fall out. After burning some plastic shields, I found that packing dirt into the hole would protect the plastic shields adequately during welding. https://www.fieromontreal.c...25.msg31819#msg31819
Also, take apart your differential spider gears and inspect. 5/6 planet gears I had were damaged in some way. In this photo, I drew red lines to show where the teeth were cracked: https://www.fieromontreal.c...25.msg32358#msg32358
Hey Pmbrunelle, do you know what the purpose is of those plastic shields is and if they are needed or where I could find a new one? I melted one when a ball of weld spatter melted it through the dirt.
Sweet I found one on ebay if I need to buy one. I do not have the P-book. I think it also kind of warped from the heat but will get a picture. The dirt was somewhat wet but I had to weld a lot to get it to shrink enough so it dried out. Will make sure it's more wet for the next 2.
Heat made the shield brittle and I broke it trying to scrape the mud off it. Also saw the PN of the shield I melted is the other shield listed in the P-book which I haven't been able to find for sale anywhere yet.
[This message has been edited by BadNewsBrendan (edited 05-02-2021).]
Think I'm just gonna run it without and see what happens. Looks like the sheild is just there to keep the plastic end cap piece of the shaft on and maybe control flow of gear oil through the bearing? At this point I will be happy just to get another 25k miles on it. Hell, I've only put about 5k miles on the car since I bought it.
Isn't there a hole going down the middle of the shaft, where the oil then lubricates the speed gears? Not sure, my memory is fuzzy.
Looks like the shield may restrict flow to the first shaft, so that enough oil remains and can continue to the second shaft, but not really sure.
If you don't really know what the shield does, omitting it seems like a high degree of half-assing (and opening the door to future troubles), but that's just my opinion.
Yeah I think you're right, there's passages in the case so it looks like the shield only let's a little oil into the bearing and the rest through the shaft. Well my only other option at this point is to buy a whole used trans and completely disassemble and try and get the shield out of that one and put it in the one I'm rebuilding or just buy a used trans and put it in the car instead and wait til it also starts leaking and then take the shield out and put it in the half rebuilt one. With how much I struggled getting the races out, neither option sounds fun. Of course I had to melt the shield that you can't buy anywhere instead of the two others that are one ebay
You're sure the ebay one won't fit? Compare the photos with what you have.
I have seen two kinds of shield, black plastic and white plastic, and I think they have different part numbers, but appear to be functionally the same. I have mixed and matched the black and white ones.
You used the P-book to determine the part number you needed?
Yeah the one I melted is just a mostly flat disk, the other two have little legs on them and different hole sizes. Thought about cutting it to match and drilling the wholes out to the same size as a last resort. The part number is molded in to the part and matches the P-book. It's on the opposite side of the case as the 14008259.
Called a warehouse that sells a bunch of NOS parts and they're going to check to see if they have one on Monday. Fingers crossed.
Originally posted by BadNewsBrendan: Called a warehouse that sells a bunch of NOS parts and they're going to check to see if they have one on Monday. Fingers crossed.
Got a response back and hes shipping it to me for $30. Pretty pricey for a small piece of plastic but if thats the only place i can get it oh well and can support a business with selling very uncommon NOS parts then oh well.
I thought about the 3D printing route but i don't know anyone that can do it and would need a material that can be heat cycled repeatedly. I doubt there are a lot of people willing to rebuild these trans so probably not a very common part to need replacing.
Well I need the 1.8 mm shim but there isn't one listed on for the Chrysler PNs and the GM ones are discontinued it looks like. I ordered the next closest 1.58mm from a Mopar parts site and they got back to me a couple days later and said they are discontinued. Saw mitsubishi has the same part number so i ordered one from on of their site and they cancelled and said that no one has them anywhere in the US. Guess i will keep looking.
I think the ones I ordered on ebay should work. With feeler gauges I measured 1.9mm gap on the tool and was going to go down one size to 1.8 like the instructions said but I also have read some people set it up for 0 end play so I think 1.9mm should be ok.
