258 to V8 swap

[Masato]

I've been wantng to swap my 258/T5 manual trans for a V8 (maybe a 350, 360 or 318). I want a manual trans and to keep my NP208.

Any suggestions? Which transmissions fit the 208?

[KivaKid]

I know for sure the T-176 manual tranny will fit the 208, and it's good one! Not sure if the T-176 will go to a V8.....

[ March 01, 2003, 08:06 PM: Message edited by: KivaKid ]

[Cecil14]

Any of the I6 trannies will bolt up to the V8 as they all used the same bellhousing pattern. (unless you go way back but we won't go there) The T-176 will not hold up to a decently built V8. Heck, they get eaten up by the 258 a lot of the time. It's not a real heavy truck tranny.

Only issue you will have by keeping your original tranny will probably be placement of the shifter. If you bolt it to the V8 you will need to move it forward and then the shifter will be under the dash. You could bend the shifter to accomidate this if you want.

Another option would be to get an NP435 from a ford. It uses the same bellhousing pattern as the T-176 and is a pretty heavy duty tranny. Might even be able to use the NP208 with it.

As for the motor the 360 would be the easiest swap. The 350 will most likely require adapters, as will a 318. The AMC motors are NOT the same as the chryo motors.

Good luck,
Anthony

[mccullough_89_GW]

don't forget to get both the drive shafts from whatever donor V8 rig you get because they are different lengths than the ones in a 258 setup...as I remember correctly...
other than the motor moounts I've heard its an easy swap

easy is relative of course....
good luck though

[jeepguzzi]

Mccullough_89_GW, the donor driveshafts may only help him if the donor also has a V8/manual tranny/NP208 set up.

This has been a real popular question. You should do a tech search. One real recent thread that covered the 360 to 258 swap is here: http://www.ifsja.org/ubb/ultimatebb....c;f=2;t=017240

[KYJ10]

I did this in my J10 and the easiest way to go is find a J20 donor tranny and case. The V8 tranny's had an adapter between the bellhousing to accomadate for the shorter engine. 258 is longer. If not, the shifter will be about 9" to far forward. Also, the 208 behind my 258 would not work cause it had different spline count than the one that went with the v8. You have to use the motor mounts for the v8, and move them up to the next set of holes on the frame. Shares a set with the shock mount. And drive shafts need to be lengthend and shortened. Or get them from donor maybe. Crossmember needs to be back a set of holes also. Dennis

[Masato]

KYJ10, I see you have a 360-T18-208. Is this a stock configuration in J20s? I'm trying to avoid adapters if possible.

Is the T18 an overdrive?

[KYJ10]

Yes, that was one of the stock configurations in the J20's. Basically any J20 with a v8 manual should be what your looking for. Your 208 has the wrong spline count for the t18. Mybe you can change the shaft, but I don't know about that. No it's not an overdrive, but it is the strongest tranny jeep ever used. There is one other possiblity. Some of the J trucks with v8's used a t176 that also had the long adaptor. Now I don't know about spline counts and all. These adapters came stock. On my setup, the is an adaptor between the bellhousing and trany, and another between the t case and trany. And these were stock. Look around the for sale or post on the wanted board. I have seen these trany-tcase packages for sale. Some people on here Im sure know other ways of doing this, Im just sharing my expirience. This was for a J truck, so with a wag or chero, the crossmember and drive shaft lengths might change, but still will all work. Dennis

[Sycho15]

You could run a Ford T-18/NP-208 combo. Heck, run a Ford 302-351 in front of it even. If your stuck on the Jeep V-8, you can use your current tranny's bellhousing to convert. There might be some input shaft length issues though.

An AX-15 5-speed from the '90-2000(?) Jeeps can take a mild V-8.

[Panther]

Masato,
If you are looking for info on the J20 T18/208 for your cherokee, check out my swap:

http://www.panther4x4.com/t18a/

This set up is extremely long, almost 4 FEET from BH to rear tcase output so I had issues with the gas tank. Heimken had Parts Mike build a custom long shaft T18 for use with a NP208 for his wag. To be honest, you are probably better off swapping the entire drivetrain from a 74-79 J20 w/ manual. That way you get the 360, T18 and Dana 20, also the front axle for pass side drop and rear axle (Dana 60) to match the front bolt pattern and axle ratio. I know this sounds like a lot of work and I personally like to travel the path of least resistance but in the end I would have been better off swapping a T18 w/ Dana 20 and WT pass side drop front axle.

There is T18a from an 80 J20 in the for sale section, not sure if it's sold or not but is in AZ. But like I said, it presents a problem with the gas tank, I will need to swap one behind the rear axle where the aux tank goes because the drivetrain is just too long to fit the "coffin" style factory tank.

We had a very thorough post a long time ago on the 258 to 360 swap with T18 but I can't few posts that old anymore.
Lee

[Panther]

I just noticed this T18 on ebay, the descriptions isn't much but the price is good [img]smile.gif[/img]
Just email and see if it's from a V8.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2405875808

[Masato]

Hey Panther,

Are all T18 setups this long? I'm not bent on AMC, any V-8 that fits the easiest will do. I can cut, weld and fabricate the frame, but parts scavenging is not my thing, it'll probably take me two to three years to complete all the parts.

[Panther]

Well, I hear ya on all the parts, might be easier if you can find a donor.

My experience is with the AMC V8 but even another motor with a T18, then you are looking at adapting the tranny for a 208. This involves a tail shaft conversion and adapter, a couple places that make these are advance adapters and novak.

No Excuses has a great price for the AA kit at $404

http://www.800-923-jeep.com

Also, Novak makes a kit for the Dana 300 / NP208 as well ($470)

http://www.novak-adapt.com/catalog/kit_183.htm

Here's my link for F*rd T18 adapted to 300: http://www.panther4x4.com/t18a/T18.html

The kits for the 300 will work as they share the round bolt pattern and 23 splines as the 208. You might have to "clock" or index the bolt holes by re-drilling the adapter but that's no biggie.

Anyway, if you find a long shaft T18 from a FSJ and get the aftermarket kit, it's pretty straight forward swap, no need for custom frame fabbing. Just the linkage and stuff mentioned already...

Edit: Oh and to answer you question, no not all T18s are this long. The 80+ J20 has 2 long adapters, 5-6" at the BH and another one about 7" b/w the T18 and 208, the Dana 20 adapter isn't that long, 3" at most.

[ March 04, 2003, 07:17 AM: Message edited by: Panther ]

[Masato]

Thanks for the tips, I'll check all the links.