which 4 speed to use?

I have a '67 CJ-6 with a 225 V6, t86, d18, d27, d44. I have a t-18 out of a 2wd early 60's Ford truck and access to a SM420 from a '66 Suburban. I know the SM420 has lower 1st gear and should bolt right to my bell housing I think? Anyone done a similar swap?

 

The SM420 will bolt to your bellhousing, but so will the T-18 with some simple machining http://www.novak-adapt.com/knowledge/ford_to_gm.htm

It's also possible to do a junkyard swap with the T-18, to avoid purchasing the expensive transmission-to-transfer case adapter. You either need a T-18 from a Jeep truck, or else the mainshaft and adapter from either a Jeep or IH T-18, plus your Ford T-18. Nick (nickmil) has posted on this a lot - if you search here and in the Intermediate forum, you'll find several posts.

 

There both nice, But I'd vote for the t-18. It's a great tranny and the shortest combo with adapter of the 4 speeds. adapter is only 1" thick. I used Novak's adapter. I put it in my 3b and love it.

 

There both nice heard good things about the 420 and have one in my garage. , But I'd vote for the t-18. It's a great tranny and the shortest combo with adapter of the 4 speeds. adapter is only 1" thick. I used Novak's adapter. I put it in my 3b and love it. Besides You have it already!

 

x2!

 

I've used both and they're both great. If you can make the t18 work without the tcase adapter then that's the obvious first choice (less parts, less $, less length). Otherwise just use whichever you can find for the lowest price and in the best condition. I think the sm420 I'm using now come out of a '67 suburban.

(Or, take Nickmils advice if he chimes in!)

 

got any photos showing how far below the frame rails the trans hangs down?

 

haven't tried either one yet, but starting from scratch I decided on the T-18 due to wider availability (SM420=Hen's Teeth in this area) and by using Jeep or international adapter, can be a much cheaper route.

the slightly lower first gear of the SM-420 was not worth the price I was gonna have to pay for one that would need to be rebuilt anyway.

$.02 asked, $.02 given. Good luck with what ever you choose.:v6:

 

I do not have photos. That SM420 is pretty big but has not been a problem. I don't use a skid plate on it (it's stronger than just about everything else on the jeep).

 

I am running a SM465 (close to the SM420) These trannys are big. I tucked mine up as tight as I could without a body ilft. It hangs down some but I also made a skidplate for it. I might have a pic around somewhere on the home computer if you still need it.