T98 Identification

I am looking for some advice regarding identifying the transmission in my 1962 CJ-5. It is a 4-speed, with reverse up and to the right. First gear is non-synchronized, and seems to be a very low gear ratio. This is mated to an L-head transplant (I assume); with the D-18 transfer case. It seems to have some problem with fourth gear, as it makes a whine/rumble in that gear only at higher speeds.

Anyway, I'm looking to rebuild it one of these days, and need to determine for sure what model I have. There is an "L1-1" cast into the top cover just to the rear of the shift tower. Right above that in the center is a bull’s-eye symbol, also cast into the top cover. To the left of the top cover there is a brass breather, in line with the bolts that hold the cover on.

If it really is the T98, I'm unsure whether I can rebuild it, as the parts are supposed to be very hard to find. Where to find those would be my next question. I'd like to keep it and use it if I can. Any help would be appreciated - thanks.

 

If it is a t98 you can get a rebuild kit from these people.
http://www.drivetrain.com/borgwarnerT18T19.html I'm sure that Herm and several others can get you rebuild parts. The gears are probably the only hard part to find.
Here are a few pages with photos.
http://www.jeeptech.com/trans/t18.html
http://www.film.queensu.ca/CJ3B/Tech/T98A.html

 

Thanks Mcruff! That parts source is great; I was afraid I had something that could not be rebuilt. It also looks as if T18 parts can be put into a T98 case too.

I still don't have a casting number that helps, but at least the case is shaped like the ones in the pictures, so I'll have to go by that for now. I can do some tooth counting when I pull it to find out for sure.

Speaking of pulling it, my FSM doesn't have a T98 section. Anyone know where to look for good step-by-step instructions for removing, rebuilding, and reinstalling a T98? I've never done any transmission work before, and feel a bit hesitant to even try. Nonetheless, being on a budget can make me pretty bold. If I think I have a fighting chance, then I'll give it a shot. With some luck, after buying the rebuild kit I'll still have enough left over for a Warn overdrive!

 

Do you really have a factory service manual? The one I have on cd has a 4 speed section and so does the book version. The cd version is 33.4 megs. It was downloaded from ******* dempsters website, he posts on here from time to time.

 

I must have the abridged version. I'll do some checking to see if I can find a complete version. At least I know where to start looking now (or I can always just buy one). Thanks again.

 

heres pics of my 98 if it helps

 

Hawk62CJ5 - those pics look exactly like what I have. Too bad it doesn't just introduce itself! It looks like you rebuilt yours from the pics; was it very difficult - more than the 'average' manual tranny?

Ok, more silly questions: about how long would a job like this take if you are doing it for the first time? Is it a weekend thing, or can I expect several working days with it before it is bolted back in again? I'll need a transmission jack - probably a rental. Do you do the r&r work right on the jack, or move the thing to some other place to clean it and do the work? If you have to take it off the jack, how the heck do you lift it without a block and tackle? I do have a paved driveway (so it won’t sink in the mud!), but I'll be doing most of this outside if possible. One last stupid question: do I need any special tools apart from the jack? I guess the FSM would tell me about that when I get a real one.

I'm sorry to ask all this stuff, but I'm pretty new to drivetrain work beyond just replacing U-joints and basic maintenance. I've done most other kinds of work to some degree or another, but have always stayed away from clutches and transmissions.

 

Why do you think the transmission needs a rebuild?

They were pretty bulletproof, so unless it is slipping out of gear, or making some bearing noises, there may be no reason to take it apart.

Taking one apart is not impossible, but it is not as straightforward as you might imagine.

The best guide for taking one apart and getting it back together was on the Dr Vern's site which is now off the air, however, someone on this site may have copied the info from his site.

good luck- and remember that in the four speed app the transfer case oil does NOT comingle with the trans oil, so filling or draining the trans has no effect on the oil in the t/c. This is different from the 3 speed.

 

Kamel makes a good point - the T98 was used in heavy trucks and buses with much higher loads and more power than a 4 cylinder CJ. Unlikely that it's worn out.

The noise you mentioned could be coming from the transfer case. Dana 18 cases are noisy anyway (they whine), and when the intermediate shaft is worn they get especially noisy. Also, worn D18 intermediate shaft is a very common problem AFAIK.

 

I'd have to describe the sound it makes as a whine and rumble. It only does it in fourth gear, and not all the time - usually when under power and over about 30 - 35 mph. I just assumed it was the tranny, as it only happens in fourth, not every gear.

Other than that, no problems. It stays in gear fine, and shifts easily. I just don't want to let it go, and end up ruining something else, like a hard to find gear, etc.

 

Mmm, not clutch. More likely transfer case than transmission.

I'd think the only problem you could have with the transmission that could make noise would be the input and/or output bearings. Don't know of any way to identify that except by inspection.

AFAIK intermediate shaft wear is really, really, really common on the D18. I have never owned a D18-equipped Jeep, so the other guys here should confirm my suspicions. The usual upgrade is to the "big hole" case and larger intermediate shaft. If you search, you'll find lots of posts about upgrading the D18.

 

I've not been looking forward to this part of the project. I suppose I could just buy a kit and rebuild the D18 only, then put it back together and see what happens. If it still does it, then I could look into the tranny rebuild. Perhaps its the speed of the Jeep causing the noise, not the gear? That might help rule out the tranny as the problem.

 

Yes.

 

Okay, I think I have my marching orders now. Thanks guys - I'll let you know how it goes. You've probably saved me a lot of $$ and time (and sweat)!

 

That is exactly what by D18 was doing when I rebuilt it, granted it was with a T90 but I think these guys are right and it is the D18 intermediate shaft.

 

In looking at your T98 it does not appear to have any gear teeth problems. They are easy to take a part and worst comes to worst I have gotten T18's out of the Pick and Pull wrecking yards for about 65 dollars. You can put the T18 guts in that T98 case as they are the same inside. But, you need to keep the T98 case as it fits that factory adapter. But, you should be able to get an overhaul kit for the T98 and rebuild it and it should last your life time.

 

You all have been very helpful; I wouldn't have even attempted this without the information available here. I am planning to remove the D18 this weekend, clean and disassemble it, and have a look at it before ordering any parts. I'll hold off on the T98 work until I can rule out the D18 after a rebuild.

Who knows what I'll find when I get into it - I will not know for sure if I have the small or large hole case until I remove it. Nonetheless, I'm guessing its the small hole kind due to the age of the Jeep. I'll probably just go with what I have, as I like the idea of keeping the Jeep original - and it may be cheaper too.

By the way, Mcruff was right - I wasn't looking in the right manual for the T98 info. I have a lot of stuff saved to various files, and just had the wrong one open.R) Thanks for the tip.

 

You would be wise to keep that T98 set-up, and rebuild what you have. It is a strong unit and again you cannot find anything better to replace it with.

 

I havnt rebuilt my 98 yet , I had just bought it when those pics were took so I was checking it out. I have to switch my input shaft so I had to take it apart to switch shafts. Its a robust tranny so I doubt its wore , Im going to replace the bearings and small parts in mine just because its apart. Im pretty sure the D18 is the source of the noise ,mine used to be loud.