transmission upgrade

I was looking for a transmission upgrade for my 1974 cj5 with a 304 amc and a T15a with a dana 20 transfercase. I would like the nv4500 not sure if you would be able to use this with a cj5 with the drive shaft angle. I have heard of the t-18 will this work with my set up.

 

SM 465 with novak adapter ,or a T18 out of a Ford truck is your best bet.

 

Rex, I have just recently aquired a '73' CJ5 with a 304 and a T-15 tranny, and have been lucky enough to aquire a Ford NP435 tranny for nothing, so my plan is to adapt this in this winter. I have emailed Novak, and they have informed my that I am going to have to change the bellhousing, specifically one from a '76' to '86' jeep from either a 258 or 304 (since the motor to bellhousings were the same for those engines),
that was against a T-150 or T-176 tranny. I also know that I'm going to have to change the clutch linkage and move the crossmember in addition to some other stuff. My choices for low gearing in the order of preference was the NP435, SM465 and the SM420. Others on the forum will probably disagree. Novak novak-adapt.com has an excellent web site, all you have to do is click on the knowledge base tab, and it gives you a excellent explanation of all the different combos that can work in your jeep. Advance adapters also has an excellent company and for ten bucks they will send you a catalog that is very informative. Their website is hard to negotiate in my opinion. Good luck and keep us posted. I'm pushing the NP435 a little because I want to get as much info as I can before I start my project. Keep asking questions, everyone on this forum is super.

 

I replaced the T15 in my 74CJ5 with a NP435 about 12 years ago. I too had aquired the NP435 for free, so that is the way I went. I used a Novak kit. I would suggest a few things.
(1). If you have ever thought about switching to a Dana 300 (quiter low range operation, lower low range gears), now would be the time.
(2). The lower the second gear is the better. You will find, especially on the street, it is nice not having to start in granny. Of course if you have low gears in your diffs, or you tires are not too large, this may not be an issue.
(3). Length of drive train. Novak's Knowledge base does tell the tranny + adapter length, but it does not tell the lengths of the required bell
housings.
(4) The NV4500 is probable too long for a CJ5, plus it has narrower gears, even with it's overdrive, than the NP435, SM465, or the Ford T18.

DocsCJ5, Please feel free to ask any questions.

 

As mentioned, the main concern in a CJ-5 transmission swap is rear driveshaft length. The shorter the OAL (overall length) of the transmission and transfer case, the better. The NV4500 is way long, almost certainly too long to be workable.

Most often, folks want that (roughly) 6.5:1 gear reduction offered by the wide ratio 4-speed truck transmissions. That's your "creeper" or "granny" gear, and it is very desirable in a Jeep.

Another downside to the NV4500 is it will probably cost way, way more than any of the truck 4-speeds that are more commonly adapted (T18, T19, SM420, SM465, NP435).

The Ford transmissions (T18, T19, NP435) are more easily adapted to the AMC engines since you can use a stock Jeep T-150 or T-176 bell.

Also, you don't need an overdrive gear in an intermediate or late CJ because the factory axle ratios are all fine for street use.

Check out the Novak site - lots of good, free and mostly unbiased info there. http://www.novak-adapt.com/knowledge/transmission_gateway.htm

 

Dvader, Thanks for your reply. I found a bellhousing from a 304 that was against a T-150, and I checked it and it fits my NP435. So far, so good. I was wondering what you had to do as far as the clutch and clutch linkage? Also what starter worked for you? I have contemplated the low gearing issue, and since all I the info I can find regarding switching the transfer case is to find a Dana 300 out of an 1980 Scout, which seems almost impossible to find so I am leaning toward the Tera-low kit from teraflex. Also it it possible to find a lower gear for second gear, or in that case can the gears in any manual transmission be changed to suit your preference? Thanks, Doc

 

DocsCJ5, I will have to get under the jeep and see if it sparks my memory on the linkage. I am pretty sure that I just used all the stock stuff and maybe the pickle fork that came with the new bellhousing. I will get back to you on that one.
I used the original starter. I used a pressure plate for a 76-80 CJ and a Ford disc. The kit will have a special pilot bushing. I moved the cross member back and dropped it 1.5 inches with blocks to reduce the drive shaft angle. I had to modify the sheet metal cover that goes over the tranny. I also had to bend the shifter around so it would clear.
The adaptor kit you are about to buy will be for a NP435 / Dana 20 or a NP435 / Dana 300. Kits are around $500, so once you make the purchase, you are vested. Yes Scout 300s are rare, but if you buy an adaptor kit it will be for the common Dana 300.
The Teralow kit for a Dana 20 is expensive. It will lower the ratio to 3.15 to 1. You can rebuild your Dana 20 and use some parts from a Bronco 20 and a Dana 18 and end up with 2.47 to 1. A Dana 300 is 2.62 to 1. The gears are helical cut, so low range is more quite than a 20. You can buy a Teralow kit for a 300 that will take you to 4.00 to 1.
Second gear in NP435 is 3,34. That is better than the 2.99 1st gear in a a T-15, so if you are happy with your street starts now, you will like the NP435 even more. If you still need a lower second gear, it would probable be better to switch to a different tranny like a SM465 or consider lowering the diff gears.
What are your diff gears and what size tires do you run?
Thanks,
dvader

 

Yep, just checked it out. It looks like I used all the original clutch linkage parts.

 

I second that, I have NP 435 behind a I6 and that first gear is a real stump puller...

 

for the np435 conversion, even though i have the 258 motor, i'm pretty sure you reuse your starter and clutch linkage. you'll need a new clutch disc, from a drof.

if the np435 was the low-range dodge version, and you find a dana 300, it'll bolt up nicely with no pricey adapter. i shelled out the $450 for the novak adapter/shaft to mate it to the dana 20, and am mostly satisfied.

re: the lower gears. depends on what you want to do (looking for a 300). i don't mind having my crawl in the neighborhood of 55 to 1, via the dana 20. using the 435 more than doubled my stock crawl ratio. after learning to "use" the jeep with the 26:1, the 56:1 seems very slow.

 

Wally, Are you saying that there is an OEM Np435 out there that a Dana 300 will bolt up to? If so, what vehicle did it come in?
Thanks,
dvader

 

i believe that to be the case.

some dodge. friend of mine has a cj-7, swapped in the 318, bellhousing and np435 out of a power wagon (no idea what year). he was looking at the output end of the dodge np435 and thought it looked similar to a dana 300 that his brother had. it matched.

caveat: there may be a factory adapter off of the np435 for the dodge's transfer case. i'll find out the deal. to the best of my knowledge, he did not use the transfer case from the dodge, it came from an 80's cj.

 

I think you'll find that the back end of the Dodge NP435 has the NP (New Process) pattern, and there are a couple of bull gears for the D300 with different spline counts, so that may work. However, the front of a Dodge NP435 will match a Dodge bell, just like the Ford NP435 matches a Ford bell. The Ford NP435 is appealing because you can use a Jeep bell (From the T150 or T176) that matches a Ford pattern. Thus there may be no easy way to connect the AMC engine to the Dodge transmisson.

I know there is a Ford 4x4 NP435 that was used in pickups that can connect to NP TCs, but IIRC the adapter is too long for use in a CJ. You may also run into this problem with a Dodge 4x4 NP435.

hth!

 

Thanks guy's you answered my questions here.

 

I'm running 3.73's and 33" tires. I want to clarify this, if I find find a dana 300 tcase, I can get an adapter kit to mate to the NP435? If so, where do I find a Dana 300, and from what years or models should it come from? Thanks everyone for all the info. Doc

 

Doc, Novak sells kits for adapting several different transfer cases to the NP435 including the Dana 20 and 300.

http://www.novak-adapt.com/knowledge/np435.htm

Jeep CJs 1980-1986 used the Dana 300. Dana 300s are relatively cheap. Check ebay and the jeep wreckers in Sacramento.

My 74 has 373s and I am running 32s, so we are pretty close.
Thanks,
dvader

 

I believe im going with a t170ft which was used in the ford f-150 and brancos its a top loader 4spd overdrive. it will bolt up to a t150 bell housing it does not have a granny gear but i will not use it for that. not sure if anyone else has done this swap let me know

 

thanks, tim.

i guess my post wasn't clear. you'd need to use the dodge motor & b.h.

that 318 is a nice motor, and fits very well in a jeep.

there's probably a way to match the dodge np435 up with a jeep b.h.; likely involving some fabrication/machining.

i have the ford 4x4 version in mine. the original adapter is WAY too long for a '5'.

wally

 

Dvader and everyone else, thanks for all the info! Doc