4.0 Swap Clutch Problems

I’m putting a 4.0 in my Jeep and having trouble with the throw out bearing. The motor is a 94 Cherokee that was a factory automatic. I bought a new flywheel and pressure plate for that motor so I could retain the CPS on the flywheel. I used a T150 bellhousing. The stock throw out bearing is about 1 1/2” away from the pressure plate fingers. I pretty sure that’s too far. Is there a thicker bearing or a better set up.?

 

Welcome from Boston.

Question - why do you need an XJ pressure plate? I would expect the bolt pattern on the XJ flywheel to be the same as the 258/4.2L. Assuming your Jeep had a 258 and T-150 originally, you could keep everything from the clutch disk back. No personal experience, but it was my understanding that the XJ and 258 flywheels are interchangeable. Seems like the XJ pressure plate does not have the proper dimensions (release arm height) for the T-150 bell and release arm.

If you can't find help here, there is a site jeepstrokers.com that has a lot of info and expertise about 4.0L swaps. There used to be a forum exclusively about these 4.0L swaps.

It would also help to list the year, model and equipment of your Jeep.

 

Thanks Timgr

This Jeep was/is a basket case. Nothing was together originally. It’s a 77 body, 77-81 frame, 94 4.0, T150 bellhousing, NP435 transmission, Dana 300 and narrowed J10 Dana 44 axles. I’m planning on using a hydraulic clutch so I wanted a diaphragm style pressure plate. The flywheel is definitely thinner and the pressure plate is about 1/4” thinner. I haven’t seen any discussions on any of the 4.0 swap post talking about throw out bearing issues.

 

Welcome to the forum.

 

Thanks Walt. It’s been awhile since I was on a forum. Looking forward to it.

 

Are the 87-90 and 91-95 YJ flywheels the same part #?

If doing this, I’d likely try to split the hydraulic portion of the swap from the engine and rig the 4.0L with the T150 matched gear.

That being said, how much meat is on that bell-housing?

I love me some AMC inline.

 

More info here:

Adapting AMC I6 & V8 Engines to Ford Style Transmissions

 

this is a neat place, and there's a lot of knowledge around here.

 

Any luck getting it to work? Getting ready to drop a 4.0 (from '92 Cherokee) in my '66 CJ5, so I'm interested to see how yours goes. The RENIX 4.0 ('90 and early) used a different fly wheel than the 4.0 HO ('91-2006). Also manuals use a different flywheel and CPS than the Autos. The ECU is different as well. Haven't heard of anyone puting a T150 behind a 4.0, but AX15 swaps are pretty common.

 

The bell pattern of 4.0L is the same as the 258, and your existing bell housing (assuming that you have a '76-79 CJ with a T-150) will bolt up to a 4.0L. The T-150 only works with the Dana 20, so it's not a suitable choice for a '66 CJ IMO. A T-15 would work.

Terminology - an automatic does not have a flywheel. It has a flex plate. The torque convertor takes over the 'flywheel' action (angular momentum) with an automatic. You need the flex plate to connect the starter to the torque convertor.

I'd also mention that an inline 6 is very long for a '66 CJ engine compartment, and it will be a struggle to make it fit. Not a smart choice when so many different and excellent V6s are available today.

Regarding the flywheel, any 4.0L or 258/232 flywheel will bolt up to these engines and be balanced correctly. The 4.0L flywheels work with the CPS (crank position sensor) while the 258 flywheels will not. Choice of flywheel should affect which starter you can use, which also involves the bellhousing design. I suspect a different starter is the main difference in this area between the early 4.0L and the 4.0L HO. You can always move the CPS to the front of the engine and go all-258 from the flywheel back.

Sorry if this seems like a list of negatives. Post up about your plans and we can discuss it. Lots of experience with these vehicles here.

 

I agree. I think getting a I6 in a 71- CJ5 will be major surgery (cross member and steering at least). Love the engines but it’s just a matter of physical length to work. Related note, I just found a 84-86 flavor of its little brother.