4 speed transmission

ok so I've come to the realization that a 4 speed transmission might fill my needs a little better than the t-90 might behind the dauntless i am trying to build into a flat fender

I have a couple questions tho. First off what was it's model #, designation, etc.? and secondly can I still use my twinstick behind it or would I have to go with a different transfer case too

I know these may seem a little elementary but I've been dealoing mostly in flatfender tech until now

Thanks for any help

Luke

 

There are a few 4 diff. speeds out there to choose from. Most of them do have adapters to bolt the Dana 18 to them. Try searching for Sm465, SM 420, T18. Those are the most commonly used.

 

Hey there, didn't know there were any other members over that way in Bama. There are several members here from Bama, firefighter mike (boaz), wsg (Hartselle) JZ (Decatur) Mark Mann (Madison) me (Albertville).
I have an sm420 to put in my Jeep and 1 thats going in firefighter mikes cj6 soon. Just finished rebuilding and adapting an sm465 to fit in Coby's cj3b with a 4.3 chevy.

 

well to tell the truth I'm up in nashville now. I graduated from UNA in florence last month and decided I had a better chance at using my degree up here, but I still have a girlfriend down there and used to live in hartselle and decatur. In fact, I got the jeep fever back in hartselle. kind of want to get my toy together and go thru a few small trails I found when I was a kid. So like I say any help is greatly appreciated.

I was kind of hoping to not have to use any more adapters sort of use a stock dauntless v6 bellhousing of some kind to a stock 4 speed. it seems from the reading I've done tonight so far is the t98 might be a good choice. I'm not gonna be rock crawling. just light trails and some woods. and still want to use it for some town usage too.

 

The sm420 and sm465 are direct bolt ons to the v6 bellhousing, the adapter is for the transfercase which the t98 has to have anyway. The t98 would more than likely have to have an adapter for the bellhousing also. They are also more scarce than the sm420 or 465. These 2 transmisions were used behind Chevy 3/4 and 1 ton trucks for 50 years so there are alot of them around.

 

:iagree:

If you do go the T98 route keep in mind that a T18 is going to use the same adapters since they both use the same case. Plus the T18s are much easier to find and get parts for.

 

OK, I'm interested now too.

What needs to be done to the Jeep to make a T18 fit? For example, do I have to move the crossmember back, cut the tranny hump, move the shifters back, shorten/lengthen driveshafts, etc?

If anyone tells me that it's a bolt on for a Fhead, I'm gonna crap a brick....

 

If you can find the rare and elusive t98 from behind a fhead yes its a bolt in. Diff. crossmember and driveshafts IIRC but you'll need to change that with any 4 speed swap.

 

Did I read right that this motor is a Dauntless? If so, there's no stock 4-speed available.* The T-98 only came behind the f-head 4-cylinder, and would be as much (more!) trouble to adapt to the V6 as any of the other junkyard 4-speeds you might consider.

The only way I know of to avoid buying an expensive adapter is to mix parts from Ford 2WD and Jeep or IH 4WD T-18s to make one transmission. You still need to do some simple machining to make this work, but it's the cheapest combo if you can find and buy cheaply all the parts.

* There was a close ratio T-18 available behind the V6 around 1971, but these are made of purest unobtainium. If you find one of these Jeeps, save it becasue they are truly rare.

 

There's no bolt in. I recall that Novak was working on a kit for the T-18, but they'd need to make a new input shaft. If you have a friend who's a machinist, you may be able to rework a J-truck/Wagoneer T-18 by shortening the input shaft to spec, but that's only a vague suggestion from me.

The T-98 or T-18 Jeeps do have different floors and different driveshafts, but I don't think the shifters move enough to need relocating.