Swapping A4LD to M50

[old409]

After my botched A4LD rebuild and threatrening to get rid of the Ranger I've cooled down and decided to swap the A4LD over to a M50. I have the pedals, switches, trans, bellhousing cover ,etc. All from a 2.9 truck.

I may be towing a trailer at some point and I'm thinking of going to the bigger clutch setup from the 4.0 engine. My truck has the 2.9 engine. I got my parts from a 2.9 doaner. What I need to know is,can I use the 2.9 cover from the doaner truck and if I can, what do I have to do to it to make it work.

Probably the best question I can ask, is the larger 4.0 clutch swap worthwhile. I don't 4 wheel, run big tires or anything like that. It's just my daily driver.The only thing is, I may tow a small rental trailer to California from Pennsylvania.

And by the way, thanks to all who tried to nurse me through the rebuild of the A4LD. I think I must have had too many senior moments when I tried it. I used to rebuild TorqueFlites and Ultramatics years ago and never had any problems. Time hasn't only passed me by, it ran over me.

 

[cocoasranger]

I love the 10" clutch upgrade that I put in my Ranger when I switched to stick. However, the stock 8 7/8" clutch is adequate for light towing and regular driving.

If you go to the larger clutch you would need the 4.0L manual starter and manual block plate (between engine and trans). Also, the pilot bearing fits in a sleeve that is pressed into the 4.0L flywheel. You would also need slightly different wiring to the starter which is easy to do.

There is a 5 pin plug into the A4LD that gets cut and the wires go to the back up and clutch interlock switch. The 5th pink wire is ignored. You will never regret going with the Mazda trans.

 

[LittleHorse]

You will never regret going with the Mazda trans.

that is until you have to do anything involving the clutch slave cylinder

I bought my BII with a bum clutch so I'm doing the 4.0 upgrade first thing. I've acquired the block plate and the flywheel, the starter is no biggie. But I wasn't aware of anything different about the pilot bushing/bearing. Can you expand on that a bit? Or did I just totally miss that when I read the TRS tech article about it?

 

[cocoasranger]

I found out the difference when I went from the A4LD to the M5OD R-1. Since there had been an auto trans originally installed I had nothing to compare it to. Luckily AllanD got me the correct parts and advice.

The 2.9L engine has a pocket bored in the crank flange into which the pilot bearing press fits. The input shaft of the manual trans rides in the pilot. The problem comes when you install the M5OD R-1 trans which has an input shaft too short to reach the pilot in the flange. This later trans is designed to have the input shaft ride in a pilot pressed into a sleeve which is in turn pressed into the flywheel. I imagine that if you expected the input to be supported by the pilot in the crank flange some damage would occur pretty quickly.

I did drive a pilot into the crank hub bore, but it did not look right, and after measuring I confirmed the problem and got a sleeve and another bearing.

When you ask for the pilot bearing at auto parts they give you a little roller bearing slightly larger in diameter than the small diameter of the input shaft. You have to get the sleeve from a salvage yard.

 

[LittleHorse]

When you ask for the pilot bearing at auto parts they give you a little roller bearing slightly larger in diameter than the small diameter of the input shaft. You have to get the sleeve from a salvage yard.

so if I acquired a used 4.0 flywheel from another TRS member, would the sleeve likely already be present in the flywheel?

 

[cocoasranger]

It would if you ask him to include it. The auto parts only looks at you funny when you describe it and quickly say "part not available". The new one I bought did not have the sleeve either same as everywhere else I checked.

All it really is is a piece of thick walled steel pipe which is a press fit for the pilot bearing on the id and a press fit into the center bore of the fly wheel. You could machine one up easily if you had a lathe, but I'm sure some TRS member has a handful of them laying around. (hint).