Servicing AMC 20/30

[JJCJ5]

I am coming up on the time for my work rotation to end. I plan on servicing the diffs, and possibly my Transmission . As far as the diffs go, I have read, that most, if not all, spray the inside with brake cleaner. Are there areas I should avoid? Can I just start at the top and spray LIBERAL amounts all the way down? My diffs have been leaking slightly, and I hope it is just the gasket. Once opened, is there to tell if it is the seal?


thanks,
JJ

 

[LongHorn]

I am coming up on the time for my work rotation to end. I plan on servicing the diffs, and possibly my Transmission . As far as the diffs go, I have read, that most, if not all, spray the inside with brake cleaner. Are there areas I should avoid? Can I just start at the top and spray LIBERAL amounts all the way down? My diffs have been leaking slightly, and I hope it is just the gasket. Once opened, is there to tell if it is the seal?


thanks,
JJ

Sounds like you're on the right track.

 

[Old Dog]

Maybe it's just me, but unless I broke something I see no need to use brakecleaner in the diff. I just let it run out and wipe the rest out with a rag.
There is only 2 places it can leak, the diff gasket or the pinion seal, it should be easy to see where it's comming from.

 

[JJCJ5]

That's understandable. I just figured it would be best since it had not been changed yet, since I had it, and there is really no telling when the PO changed it.

And, Fel-pro gaskets seem the way to go, according to some of the boards. These are cork, correct?

thanks
JJ

 

[Old Dog]

Cork, I think so, I don't remember what brand I bought last time, what ever auto zone had I guess.
I change mine acouple times a year to keep the water out.
I always use the blue rtv on both sides of the gasket and I never have a leaking problem.

 

[JJCJ5]

I have called around a cpl of places. Everyone asks me if it is 10 or 12 bolt. Why? I am more than positive that I have an AMC20 and it had 12 bolt. Could they be showing the Chrysler 8.25? Has anyone had this problem? I hve a chart with the covers on it at home, I am at work. The chart I found pretty quick was a gasket chart. And both the AMC20 and the Chrysler 8.25 are very similar, except the 8.25 has 2 less bolt holes.


thanks
JJ

 

[Buuushman]

Most likely they are looking up your drivetrain and the computer tells them there should be a G.M. 10 or 12 bolt rear behind your 350- 350 setup. you may be better off looking up the part # yourself and ordering that way. Unfortunately, most parts store clerks are useless without their brain box on the counter.

 

[Old Dog]

I've been asked the same thing, tell them 12 bolt.

 

[IOPort51]

Most likely they are looking up your drivetrain and the computer tells them there should be a G.M. 10 or 12 bolt rear behind your 350- 350 setup. you may be better off looking up the part # yourself and ordering that way. Unfortunately, most parts store clerks are useless without their brain box on the counter.

When they ask you what engine you have tell them a Rolls-Royce V12, or "I haven't decided yet". Have some fun with them.
I called AZ looking for a Haynes service manual for a 92 Cherokee; they asked what size engine I had.

 

[JJCJ5]

I have now gotten the cover off the rear, and it has drained. My question, I have the Fel Pro gasket RDS 13889. It does not have the bolt holes. But, my cover does not have a "seam" to set it in, if that makes sense. The cover has a little groove running in between the bolt holes. Whatever the PO used was orange. And they used quite a bit of it.

Does the gasket sit, just inside the bolt holes?

Here is the link to the pic
http://i531.photobucket.com/albums/dd357/huskerfoos/100_1795.jpg

 

[IOPort51]

I have now gotten the cover off the rear, and it has drained. My question, I have the Fel Pro gasket RDS 13889. It does not have the bolt holes. But, my cover does not have a "seam" to set it in, if that makes sense. The cover has a little groove running in between the bolt holes. Whatever the PO used was orange. And they used quite a bit of it.

Does the gasket sit, just inside the bolt holes?

Here is the link to the pic
http://i531.photobucket.com/albums/dd357/huskerfoos/100_1795.jpg

the housing has the groove, not the cover. Don't be ashamed to use the RTV and use it on both sides of the gasket. This is where I use a bit of brake cleaner to clean off the housing and cover where the RTV needs to stick.

 

[BajaEdition]

I hate leaks and I super clean gasket surfaces, I try to be gentle though using a putty knife and then brass brush. I do believe in covering all areas you do not want peices of brass in first. then I use RTV on both sides of a gasket.
Oh and when inspecting the inners of that diff, do not use brake cleaner unless you need to get a close look, I keep a squirt can of mystery oil handy to squirt surfaces I want to look at. I figure it is a lubercant and not something designed to break down oil, but thin enough to clean a surface, plus if any remains in the Diff, it is an oil.

 

[JJCJ5]

Thanks IO. What I want to get now is the Blue RTV gasket maker? And I assume just a small bead, enough to adhere it to the housing and then to the cover, correct? I have read somewhere that those who used strictly a gasket maker, wait a day before driving. Should I do this? Any other tips?

thanks
JJ


And by the way, to show my mechanical abilities. I removed the cover, and then a slight panic ensued when I realized there wasn't a fill plug in the cover. And, I hope it is what I removed on the opposite side of the housing. haha

 

[LongHorn]

Thanks IO. What I want to get now is the Blue RTV gasket maker? And I assume just a small bead, enough to adhere it to the housing and then to the cover, correct? I have read somewhere that those who used strictly a gasket maker, wait a day before driving. Should I do this? Any other tips?

thanks
JJ


And by the way, to show my mechanical abilities. I removed the cover, and then a slight panic ensued when I realized there wasn't a fill plug in the cover. And, I hope it is what I removed on the opposite side of the housing. haha

The fill plug is on the side of the housing.
The black permatex is for oil resistance.

 

[IOPort51]

The fill plug is on the side of the housing.
The black permatex is for oil resistance.

I can see where the the Permatex is probably better than the RTV for oil resistance, it is kind of messy but so is the RTV. My first choice is Lock tite 515 gasket eliminator. It is pricy. But it goes a long way. bottom line, if you don't get the oil off the gasket surface it will not seal. and cross torque the bolts even and slow. I also am a big fan of lock tite thread locker with or with out lock washers.

 

[LongHorn]

I can see where the the Permatex is probably better than the RTV for oil resistance, it is kind of messy but so is the RTV. My first choice is Lock tite 515 gasket eliminator. It is pricy. But it goes a long way. bottom line, if you don't get the oil off the gasket surface it will not seal. and cross torque the bolts even and slow. I also am a big fan of lock tite thread locker with or with out lock washers.

Make sure to use light or medium Lock Tite or you'll never get it off again.

 

[JJCJ5]

OK guys. Just got my cover back on. Used the RTV on both sides of gasket, maybe 1/8 bead. Sort of resembled a finger painting haha. Andyways, I hand tightened the bolts, and the ones that wouldn't hand tighten, I snugged up with the ratchet, the lock washer could still be moved. Will wait about an hour snugg them up again.

When should I torque them?

I think While I am waitng for that, I may go ahead and service the Transmission since has been leaking too. Hopefully it is just the pan gasket leaking.

thanks
JJ

 

[LongHorn]

OK guys. Just got my cover back on. Used the RTV on both sides of gasket, maybe 1/8 bead. Sort of resembled a finger painting haha. Andyways, I hand tightened the bolts, and the ones that wouldn't hand tighten, I snugged up with the ratchet, the lock washer could still be moved. Will wait about an hour snugg them up again.

When should I torque them?

I think While I am waitng for that, I may go ahead and service the Transmission since has been leaking too. Hopefully it is just the pan gasket leaking.

thanks
JJ

Your probably good to torque it up now.
Good luck with the tranny.

 

[JJCJ5]

OK, I am stumped. I drained the fluid to the Transmission , and pulled the pan. I got my new gasket, filter out, and realized the filter is different. The one I was sold, has a filter somewhat shaped like the drain pan. The filter on the traans is square. Also, I haven't cleaned the pan and set the gasket on it, but by me and the wife holding the gasket over the pan, my gasket is bigger than the pan.

I looked and found Transmission info. Mine isn't stamped like this. I took a closer look, and found a number on the piece that the filter attaches to, which I think is the valve body, acording to wittrans.com. There ais also, no number on the governor. Anywhere else I need to look?


thanks
JJ

 

[LongHorn]

OK, I am stumped. I drained the fluid to the Transmission , and pulled the pan. I got my new gasket, filter out, and realized the filter is different. The one I was sold, has a filter somewhat shaped like the drain pan. The filter on the traans is square. Also, I haven't cleaned the pan and set the gasket on it, but by me and the wife holding the gasket over the pan, my gasket is bigger than the pan.

I looked and found Transmission info. Mine isn't stamped like this. I took a closer look, and found a number on the piece that the filter attaches to, which I think is the valve body, acording to wittrans.com. There ais also, no number on the governor. Anywhere else I need to look?


thanks
JJ

I'd take the pan & filter to NAPA & see if they can match it up.