Manual Transmission Fluid Leak, How to Replace Gasket betw Trans & Transfer Case

[gcaiola]

I changed the fluid in my 1994 2.3L, MANUAL, 5-speed OD transmission. Either by coincidence, or because of putting new fluid in, a leak began between transmission & transfer case. I can even see that it's deteriorated (can't see gasket between the two metal surfaces), at several places. So it leaks down and I refill as needed (every few weeks). It's run fine for several months this way, but I'm getting tired of it and want to prevent bigger, future problems, and stop dripping fluid everywhere.

In colder weather, it's sometimes hard to get into gear when first starting car, and slightly loud when car is started. Both symptoms appear to be consistent with low fluid levels. Questions:
What's the best solution here? Can I just separate the two transfer case surfaces and use a proper gasket/sealant compound? I'm assuming this is going to be VERY HEAVY once I loosen bolts. Are both sides otherwise supported or when I loosen is the going to be a bigger problem for me to manage?

If I get an actual gasket designed to fit, I'd either have to cut top of gasket (to get around driveshaft) or disasseble shaft (which I'm definitely not going to do).

Any help would be much appreciated!

 

[ForOffRoadDriving]

first i would make sure that its the gasket thats leaking, these transmissions have a tendency to leak out of the 3 rubber plugs in the top by the shifter, which will then run down and cover everything. if youre leaking fluid between the trans and transfer case then you probably have a bad seal on the transmission side, since the two dont share their fluid (spearate fill and drain holes on both trans and tcase). you will have to remove the rear driveshaft in order to get the tcase off, theres no way around it. the tcase is light enough that you should be able to handle it alone, but another pair of hands wouldnt hurt either. once its off you can make your own gasket out of gasket paper, try to find one pre-made (good luck), or use silicone sealant to seal them.

 

[ForOffRoadDriving]

http://www.therangerstation.com/tech_library/shift_rail_plug_maintenance.htm
the dorman part no. for the freeze plugs is 555-018

 

[dorman68]

first i would make sure that its the gasket thats leaking, these transmissions have a tendency to leak out of the 3 rubber plugs in the top by the shifter, which will then run down and cover everything. if youre leaking fluid between the trans and transfer case then you probably have a bad seal on the transmission side, since the two dont share their fluid (spearate fill and drain holes on both trans and tcase). you will have to remove the rear driveshaft in order to get the tcase off, theres no way around it. the tcase is light enough that you should be able to handle it alone, but another pair of hands wouldnt hurt either. once its off you can make your own gasket out of gasket paper, try to find one pre-made (good luck), or use silicone sealant to seal them.

I agree with ForOffRoadDriving, check those shift rail plugs, they leaked on both of the Ranger's I have owned and my coworker's.

 

[LittleHorse]

the M5OD has a rear seal, there isn't fluid between the transfer case and transmission. If it turns out not to be your shift rail plugs, it sounds to me like your tail shaft seal is leaking, allowing fluid into that between space, which has a channel cut in the bottom to allow fluid out so you know its leaking.

 

[gcaiola]

thanks for the input....+ a follow-on question....

1st of all, thanks, for the great input. I'll check out the shift plugs. Their replacement part, shared by "ForOffRoadDriving', is : http://c2c.activant.com/ctoc/index.jsp?ID=dBS16GCw.CU5_Oy9_CUdGM2xEU186AlEMSnFSQU0A

I don't understand what their purpose is, and especially don't know why they're not permanently sealed initially (rubber plugs), but should be permanently sealed to repair (metal plugs). That replacement part image looks like something I'd have to hammer in (permanent seal), so I guess I couldn't do this without lowering transmission. Is that true? Assuming this is even the problem, I'm hoping to reach from below without removing transmission, or get to from the top side--from inside the car. Any chance of that?

Also, someone from the "how to" link ( http://www.therangerstation.com/tech_library/shift_rail_plug_maintenance.htm )that was shared says he pulled shift boot from inside, removed plugs, put RTV around them and reinstalled. Any comments on this?

Thanks again for the info on these questions. It will help me take the next step....

 

[Roger]

I had to replace the rear output shaft seal on my Jeep, but the same mostly applies to whatever you are working with. 2 people is always better than 1 for putting the transfer case back in. Its not so much heavy as just an awkward shape to handle.

 

[ForOffRoadDriving]

you MAY be able to put the plugs in from the top, youll need to remove the seats and pull the carpet back to gain access to all the bolts on the floor plate. i used a socket to drive the freeze plugs in, and ill bet that if you cant get to them from the top to drive them in (not enough space to swing a hammer) you could use a wobble drive with extensions (not a swivel) and have someone hold the socket and plug in the hole from inside the truck, while you smack it from the bottom. you may need to lower the trans a little by removing the trans crossmember and supporting it with a jack (that will require removal of the driveshaft also). i used permatex aviation grade form a gasket, part no. 80019 to seal the freeze plugs.

check out the images on this page of my build, it will show you the space between the trans and t case and the gasket i made as well as the freeze plugs before and after.
http://www.therangerstation.com/forums/showthread.php?t=37621&page=20