T98 To D18 Question

Currently I have a 225-T86- Big Bore D18. I have come across a T98-D20. I would like to go to a 225-T98-D18 if possible without adapters. The trans was behind a 327 or so it says on the attached bell housing.

Is swapping this over without adaptors feasable or would I be better off to find a Ford T18 and buy an adaptor for the trans to tcase?

 

AMC 327? The AMC 327 is nothing like a Chevy. That would make sense because the T98-D20 was available with the '65-'67 Wagoneer and J-truck (FSJ). How long is the input shaft? Later V8 FSJ have very long input shafts, and I expect the 327 version does too.

Go with a Ford or Jeep T-18.

 

Swap the guts of your 18 into the 20 and make a 'super 18'. Ive seen a few threads here on that. look at my build for the front adapter number for the t98 to bop bell. I have seen a few recently. Measure your mdg stickout and check it for compatibility.

I will be tackling the conversion as soon as i get my engine back and wrap up some vacation time. I assume i will need to fab a few things.

 

J- truck and Wagoneer transmissions have been a sucker hole for many a buyer wanting a 4 speed transmission. Even worse when a seller makes you believe that "all you gotta do is swap the input shaft and you got a $1000 transmission" It is far better to find a Jeep T-18 out of a 77-79 CJ that has the right input shaft length to go to a GM bellhousing in the first place. If money is not a factor however, anything can be done if enough cash is thrown at it to source the right parts. Herm the Overdrive Guy sells complete rebuilt units that are ready to bolt in also.

 

Yes, it appears to be from an early J truck w a Vigilante 327

 

Also, the transmission pages on the Novak site will help you a lot.

 

Howard, what do you have against the T98? Should I know something, since that is what I have? Just curious...

 

The M-715 and kin have a divorced transfer case. Not much value in CJ-world...

 

So the issue is with the M175 version? What do you mean by "divorced xfer case"? Haven't heard this term before. Thanks...

 

One more question...

Since the differentials on the 62 CJ-5's are so far offset to the right, am I kind of stuck with the T98 and D18 when I want to change engines? Due to the build of the T-98, would I be better going with a T-18 or similar, or should I just sell this one intact and look for something else? I respect your opinion greatly, so I have to ask.

Thanks.

 

Divorced: a short drive shaft between the transmission and transfer case.

If you can find someone who wants the F134/T-98 setup, selling it complete would make sense. Pretty sure Advance makes an adapter for the T-98 to GM bells, so you could possibly put that together. Likely a $500 kit though.

It is possible to put a T-18 swap together with junkyard parts. No personal experience, but with minor machining you can combine a Jeep or IHC T-18 main shaft and adapter with a Ford case and get a combination that will bolt to a Ford or GM bell and a Dana 18. It is also possible to swap the input shaft on a Jeep T-18 for a Ford input and bolt the Jeep case to a GM bell. Or you can use a Novak or Advance conversion kit with one of the more common truck 4-speeds - T-18, T-19, NP435, SM420, SM465. Lots of info about the bellhousing side of the swap on the Novak site.

Lots about this in the archives... it's a popular topic.

 

The T98 can be made to work but the maindrive gear (input shaft ) is a huge detriment.
A modified Borg Warner T18/T98 is the shortest feasable truck type 4 speed combination behind a GM or any engine for that matter.
Your T98 input will be too long but can feasably be shortened for use without bellhousing adapter.

Novak and most others all highly recommend modifing the Ford version of the T18 to D18/D20.
I much prefer using a Jeep version of the T18.
Basically I find it to take less effort as they function equally well.
I modify the Jeep T18 case so it bolts direct to a standard unmodified GM bellhousing.
In fact I just built 2 T18 units and they both bolt direct to the short Dauntless bellhousing.

The T18/T98 always uses an adapter plate to the D18/D20 transfer case.
There exists no practical way to eliminate that adapter plate.

 

Yeah, but you seem to keep a lot of this stuff in your head and it saves me time. Hope I didn't make you feel cheap and abused...LOL.
I am going to save a lot of the stuff in here and later when I have more time, I am going to go back and read the compilation and make a decision. Thanks for your time...

 

Oldtime,,,, A lot of good info here. I like my Jeep, but I would rather have something that I can actually drive to the site where I am going to go offroading. Trailering, or towing just seems to be a lot of hassle. But on the other hand, my tow vehicle would be an Xterra Pro-4X, which is, in and of itself, a very capable vehicle. Should the CJ break down, I would most likely be able to get back to it with the Xterra, with whatever I needed to fix it.
Decisions, Decisions...

 

I would, but I had to rebuild the xfer case and replace a lot of leaky gaskets and seals. So giving it away would kind of not be an option