4X4 conversion of W series truck

[lostviking]

I've been toying with an idea, at least in my mind. Instead of putting a Scott's Hot Rod shop IFS in my '46 WD15, I've been thinking about a 4X4 conversion. The thought is to use a Cherokee front axle assembly, convert it to leafs and use the factory leaf spring (at least to start). Put a steering box from a Cherokee (or other compatible one) in front of the axle. I can box my frame when I do that. Use the transmission and transfer case from the same. I can put the transfer case lever where the stock e-brake lever is now. I saw where someone used back seat or maybe it was third room seats from a Mopar to replace his bench seat, and that not only looked great, but left a spot in the center for a pull handle for the rear e-brakes in my existing Cherokee rear.

 

Don't know if I can adapt an AX15 to the bellhousing on the flatty or not. It's not a bad engine, so why not keep it if I can. Otherwise I have owned and like the 4.0 Jeep engine quite a bit, and that swap has been done, so it can be done. If I did, I'd use the whole Jeep pedal assembly and master cylinders mounted to my firewall.

 

Thoughts? Anyone done any of this? Adapting the stock steering column seems like the least difficult part. Keeping the flathead would mean no changes to the electronics. Crazy?

[billrigsby]

6 hours ago, lostviking said:

Otherwise I have owned and like the 4.0 Jeep engine quite a bit, and that swap has been done, so it can be done. If I did, I'd use the whole Jeep pedal assembly and master cylinders mounted to my firewall.

Thoughts? 

 

The Chrysler 4L straight six is almost bullet proof, I have had several, the last was a 94 ZJ (Grand Cherokee),

if you do use it, replace the o-ring behind the oil filter housing/adapter, it is a known week spot.

At least while in situ in the Jeep it is a PITA to get at, might not be so bad in an older Dodge.

 

 

[Old CWO]

I have pondered a 4x4 conversion a bit myself and would like to see one done similar to what you are describing.  The XJ D30 high pinion front axle with factory leaf springs seems like a sound approach, especially if you already have the Cherokee rear. YJ, TJ and ZJ front axles could also work but XJ is in my opinion the best of the bunch.  You would want a 95+ high pinion axle for the larger u-joints and lack of center disconnect. 

 

Keeping the flatty for power is fantastic but I'm not aware of an easy way to run the AX15 Jeep trans behind it.  With available adapters, I think it is feasible to bolt up a S10 T5 in 4x4 flavor with associated xfer case.   I would probably favor the NP231C with aftermarket slip yoke eliminator. 

 

With 4X4 trucks, tire size drives almost everything so pick your last set first.  Given the strength of the drivetrain proposed, 33s would be absolutely the maximum reasonable size.  I like the idea of narrow steel wheels and LT215/85R16 in a very aggressive tread pattern for that old school skinny/tall look you would see on early 4x4 trucks.?

 

[lostviking]

Not many applications used the T5 in a 4x4. Those were non-world class such as 4 cyl Jeeps in the 80's I've read. They only come in front of Dana 300's also. I need to get some better information regarding the input shaft on the 3 spd stock transmission. There are several length input shafts on the AX15. Lots of information is still needed, and I'm getting ready to drive out of state to see my Mom for Thanksgiving. Be a week or so before I'm back trying to find more dimensions.

[billrigsby]

If you do go that route,

I have the 94 XJ and ZJ Shop Manuals and ZJ Parts List in PDF.

Along with other PDFs.

 

Just ask.

 

 

[Old CWO]

1 hour ago, lostviking said:

Not many applications used the T5 in a 4x4. Those were non-world class such as 4 cyl Jeeps in the 80's I've read. They only come in front of Dana 300's also. I need to get some better information regarding the input shaft on the 3 spd stock transmission. There are several length input shafts on the AX15. Lots of information is still needed, and I'm getting ready to drive out of state to see my Mom for Thanksgiving. Be a week or so before I'm back trying to find more dimensions.

Not Jeep T5, Chevrolet.  The S10 T5 is adaptable to the Mopar flathead trucks with a fairly simple kit.  The T5 was in plenty of 4 cyl. and V6 4x4 S-trucks. You would use the Chevrolet transfer case married to the T5. There's some interchangeability on GM transfer cases of that era so you have options. The GM NP231C is very similar to the Jeep and NP231 and just as reliable, even taking some of the same beef-up parts.

Yes, the S10 T5 is NWC but that isn't really a problem behind a flathead.  The NWC is more maligned than it deserves - the root causes of most issues are incorrect fluid and lack of positive stops on the shifters.  Both of those are easily corrected making the NWC T5 more than fine for less than V8 applications.

Yeah the AX15 is a better transmission if you can figure out how to mate it up but the T5 is low hanging fruit if you're keeping the old engine.  Either way, please keep the board updated if you proceed.  It's a cool project

[41/53dodges]

I forget which of the FacePlant pages it is, but there's a guy doing almost exactly what you're thinking of.

XJ Axles, engine, complete driveline. I'll have to see if I can find it.

Fairly certain he chopped the firewall to make it fly.

 

As for the T5 with the flatty, XJ's are driver side drop and S trucks are as well, Jeeps are passenger drop.

Grab one with its case from a pre 1987 truck with a 2.8, or swap the tcase for one with a mechanical speedo

Adapting the T5 to the engine ought to all be the same as normal, providing you use one with the Muncie pattern rather than the Ford pattern.

 

That said, one hitch in that whole plan, the driver side tcase will probably hit your fuel tank.

 

Maybe a wrangler T5 with its shorter tailhousing and some other case?

 

One last thought- if you want to go old school 4x4, there's an M37 chassis in a boneyard near me. that'd be slow as anything, but cool nonetheless

[QEC]

Using the AX15 is doable if you adapt at the block instead of the bell/trans face. The only problem with adapting at the block is losing the rear mounts currently on the oem bell but, considering the amount of fab work you are contemplating, that should be easy to fix.

[Old CWO]

20 hours ago, QEC said:

The only problem with adapting at the block is losing the rear mounts currently on the oem bell...

 Once you get to this level of fab and modification, I really think you should strongly consider just going straight to a V8.  Everything you have to mod for installing a non-native L6 is pretty much the same as a V8 swap.  Given the ubiquity of V8 parts and upgrades, your total cost might even skew lower.

[kencombs]

I don't know  how my mod would translate to an earlier chassis, but I used a 60 crossmember under a 60 clutch housing with the correct mounts on my 56.   That housing is the correct depth for a later transmission, and is drilled for the L6 and early poly/hemi engine also.   So, even though I'm keeping the six, I could later unbolt it and drop in an early V8, maybe even an LA version with some machine work.   My trans is an A833OD which has a front bearing retainer sized to fit the clutch housing.  I plugged the unused holes in the housing, welded some bosses onto it with Nirod then drilled and tapped for the newer trans.  I'm pretty sure the same method could be used to bolt up most transmissions without an integral clutch housing.   Since that housing has a big opening for the retainer a reducing ring may be needed for some trans. 

Edited November 26, 2023 by kencombs

[lostviking]

I've been on a trip to TX for Thanksgiving, so no contact since last Monday.

 

I agree, once I got this far a V8 is about as much trouble. Of course, I don't think it's any trouble My other thought on that is that the V8 is probably shorter overall than the 4.0, I'd have to check but I think that makes sense.

 

I wasn't worried about losing the rear mount if I kept the flatty, I was going to see if I could adapt the trans at the rear of the bellhousing. I don't know what the input shaft length is for either transmission right now, and I'm that early in the thought process. I do know I'd rather convert to 4x than spend as much on a IFS. If I did that, it would have to be the Scott's unit with is NOT a MII style, but rather one engineered specifically for the truck. It's about $5000. But that is the complete front end with motor mounts. Just connect the steering shaft. But a nice 4x since I didn't buy a new Jeep and I'll want 4x4 when  I retire and escape California...

 

Whole lotta thinking and looking around. It's great to hear from anyone who's done it, why learn from your own mistakes...

 

Have a good evening everyone. 5:50PM and just got home a half hour or so ago. Gotta find where the cat is hiding and get him relaxed. He doesn't like being left alone.

Edited November 26, 2023 by lostviking

[lostviking]

Does anyone have the measurement for the input shaft stick out? The distance from the front face of the transmission to the tip of the input shaft? If anyone has or knows someone with a Cherokee, the distance from the rear of the bell housing face to the rear of the transfer case. I'll see what I can find.

 

The fuel tank is definitely something I didn't think of. That might put a wrench in this. The pedals aren't an issue. I was thinking of using the entire assembly from the Cherokee anyway and mounting them to the firewall. I like the idea of the master being where it's easy to get at. That means the stock bell is not an issue. I can make something work for the rear mount. Still in the thinking stage of this idea. Only just mentioned it to the wife, but we were driving cross country so I don't think she was really listening

 

[kencombs]

20 hours ago, lostviking said:

 

 

I wasn't worried about losing the rear mount if I kept the flatty, I was going to see if I could adapt the trans at the rear of the bellhousing. I don't know what the input .

 I actually wanted to do an automatic but the issue I was concerned about was not so much loosing the rear mount as  how to re-engineer the front one.  all the torque reaction resistance in our flatties is in the rear.  Without those widely spaced rear mounts the front would allow a LOT of rotation.

[lostviking]

What I meant was that I was still planning on using the stock bell housing. One thing I hadn't thought of was what 41/53dodges pointed out, the gas tank getting in the way. Have to take a look at that for sure before I spend much time on this.

[Los_Control]

I'm just smart enough to know I'm not smart enough to figure out transmission conversions on my own.

I can buy a kit and follow directions, figuring out pilot bearing dimensions, shaft lengths & diameters ..... throw out conversions .... way out of my league.

 

Seems to me, you almost need to have all the pieces at your disposal just to measure & mock up ... just to see if you can make that trans work with your bell housing.

 

Just tossing out my opinion, I love the idea of keeping a truck original and using it as it was designed to be used.

I feel I can keep mine original because 90% of my driving is in a small town with population of 2500 people and speed limits up to 50 mph.

I can drive to neighboring towns using side roads ..... I can use the stock truck as it was designed to be used.

 

If I were to do all the fabrication to convert it to a 4x4, I think I would want the jeep 4.0 motor to go with the total package. To me it makes it complete.

I would probably want to run some mild 31 x 10.50 - 15 tires ... a little taller, wider then stock .... While I would not want to beat it out on the trails, I would like to be able to use 4x4 when I thought I needed it.

I'm not saying the flatty will not do the job of turning both axles with taller tires ..... boy it sure will be working hard .... and wearing out twice as fast.

The flatty would be a serious weak link if it was left in place.

 

I'm just suggesting in my opinion, the 4.0 needs to go in with the rest of the package. .... It would really change the abilities of the truck and allow you to use your new drive train as it was designed to be used. Freeway driving, trailer towing, lite off road or winter driving in ice & snow .... many trips to the ice cream shop.

 

I will not say you are improving or harming the value of your truck ..... IMHO if you had 2 exact same trucks with the same 4x4 mods and your excellent fabrication skills to build them ..... The truck with the 4.0 would sell faster for more money then the truck with the flatty. If you are going in, go all the way not 1/2 way.

Just my opinion.

[lostviking]

Opinions are welcome. One that was brought up was the expense/effort of doing a 4.0 or just doing a V8. The V8 might fit better due to the overall length. I don't know right now if that's true, but the V8 comes in front of a 5spd and transfer case that would be just as available. So I'd be leaning to the V8 side. the fuel tank clearance is what I haven't looked at yet. Need to crawl under my truck and take some measurements. If I've given anything away with this truck, it's that I think about things and take it slowly. It's nice to get on here and ask questions, and hear what other people might have done, or just another perspective.

[lostviking]

Haven't found all the information I need on the stock trans, but since T5 swaps happen all the time...it has a stick out of 7.2 inches. The AX15 has a stick out of 7.5 inches, so it's in the ball part of doable. Need more information. There are also different stick out lengths for the AX15. Bell to transfer case is around 16.5 inches...still looking at this.

[Old CWO]

7 hours ago, lostviking said:

Haven't found all the information I need on the stock trans, but since T5 swaps happen all the time...it has a stick out of 7.2 inches. The AX15 has a stick out of 7.5 inches, so it's in the ball part of doable. Need more information. There are also different stick out lengths for the AX15. Bell to transfer case is around 16.5 inches...still looking at this.

I have a 52 truck 4 speed sitting in the garage that measures 7 5/8 inches.  I am under the impression the earlier trucks are the same, perhaps someone more knowledgeable than me can confirm.

 

You may want to double check your info on the AX15, IIRC Jeep and Dakota AX15 are 7.8 input shaft length.

[lostviking]

https://www.novak-adapt.com/knowledge/transmissions/manual/ax15

 

[Los_Control]

On 11/28/2023 at 9:55 PM, lostviking said:

Opinions are welcome. One that was brought up was the expense/effort of doing a 4.0 or just doing a V8. The V8 might fit better due to the overall length.

I thought about this myself .... I really was unsure to share my view point. I actually had a 1972 CJ5 jeep that had a mild build headers, 4 bbl, cam, 2" lift .... It was fun when you are 25 years old.

It simply had too much power and I always  broke things with it. ... I loved the way the V8 sounded when I opened it up .... When I should have been crawling on the trail, I would whap the throttle and end up sliding off the trail and bent the rockers on the body.

 

I loved to do wheelies over beer cans in the parking lot on Friday night .... On my honeymoon we were pulled over at a machine shop replacing the bearings in my rear end in the parking lot .... while on our way to a cabin on the beach we reserved. The stories go on & on about my jeep .... I just loved the way the engine sounded and liked to hear it.

 

In my 30's I bought a 1979 Toyota 4X4 pickup, a little 4 cylinder and I had so much fun with that truck ... I drove it for several years, I never broke anything or had to be towed home. It simply never had enough horse power to break things. ..... It was not exciting if I stepped on the throttle to hear it roar.

 

So I'm not a big fan of nice sounding V8's in a 4X4  .... I'm older now but not sure I could trust myself. .... I love the way my sbc sounds when rowing through the gears to get on the freeway .... I'm not sure I will ever grow up ..... while others have more restraint then me.

 

A mellow sounding 4.0 would probably have just as much HP as a nasty V8 ....... but not nearly as tempting to open it up ....

 

That's my story & I'm sticking to it.

 

[Old CWO]

6 hours ago, lostviking said:

https://www.novak-adapt.com/knowledge/transmissions/manual/ax15

 

Manual – Quality Engineered Components

[Old CWO]

5 hours ago, Los_Control said:

 

 

In my 30's I bought a 1979 Toyota 4X4 pickup...

 

One of the coolest looking and capable 4x4 trucks ever sold in the U.S. market.  I wish I had the bankroll to buy and DD a stone stock long bed '79 Toyota 4x4.  What an awesome little truck; it probably helped cement Toyota's reputation for American consumers.

[lostviking]

There are different lengths. If I'm going V8, that might not be the best transmission anyway. Does anyone know the length of the input shaft on the stock 3spd?

Edited December 1, 2023 by lostviking

[lostviking]

Hmmmm. Have 3.55 gears in the rear end, and fronts with that are easy to find. Thinking that I don't need overdrive...which brought me to NV435 transmissions. Nice and short, shifter seems to be nicely placed and easy to adapt to a NP231 transfer case. I really need to slide along the ice cold garage floor and see if this was all just a brain tease. Where is that gas tank?

[lostviking]

OK, looked under the truck. The elephant was there, called the fuel tank. Anything is doable, but to get room for the transfer case, the fuel tank would have to be moved. I think I could move it to the other side, move the filler neck to that side of the cab, run the exhaust down the drivers side since the tank was over there, but that means moving the battery...too much has to be done I think to make it reasonable.

 

If I want a 4x4 with this body, I think the only reasonable way to to do a complete frame swap. Not gonna happen.

 

It was a nice brain exercise, but I don't believe this is worth the effort for me. I'm back to an IFS from Scott's Hot Rod shop. I know he can do it for the flathead, but...just don't know anymore. One thing I did learn about was some of the great transmissions I could switch to, if I wanted. T5's aren't IMHO the best swap. There are some nice truck transmissions, like the NV435, which are short, top shift and have the same, or similar stickout. I have to wonder why people have gone to the T5 in the first place.

 

Anyway, I'm not doing a 4x for the reasons above. If anyone else thinks it's still worth the effort, I'd love to watch your project.

Edited December 2, 2023 by lostviking