5.3/AW4 becomes LSx/T-56-

[IXNAYXJ]

Time to come clean about the adventures with our experimental 5.3/AW4 adaption: We couldn't make it work. Once the Chevy V8 was all the way up to full power (turns out a RENIX era fuel pump will NOT give it enough gas, but a 97+ will) the AW4 threw in the towel. We could only manage about 2 hours per transmission, and this is with two trans coolers and an upgraded valve body from Child9.

Unfortunately, we don't think the problem is with the transmission itself, but rather with our adapter. It was far more complicated than we thought, and we went through 3 different variations. We simply couldn't measure or machine to the tolerances required which resulted in metal on metal interference, resulting in incredible heat. Our trans temps were above 400 degrees for extended periods of time, and the transmission itself never slipped. We're still not sure what finally let go, but it was violent:

In-car video when transmission explodes, only 10 minutes to the checkered flag

Sadly, here's how we spent much of our last race:

At least we looked good at night when the parties were going on:

So we've decided to abandon the concept altogether. An obvious solution would be throwing in a 4L60E and going back to pure automatic-land, but a couple years ago we bought a wrecked '01 Firebird WS6 and sold off all the parts...except for the T-56. It's been sitting in the shop for years mocking us as we struggled with the AW4, so now we're going to put it to the test. It should also free up some more power from our GMC Van motor. We think this is all we'll need to do the swap:

-Shorten & Balance our (or the Firebird's) driveshaft, $50
-Possibly buy an adapter U-Joint (combo sizes) $30
-Fab cross-member mount $5
-Fab clutch master mount for firewall $5
-Adapt the MC pushrod to the pedal $5
-Clutch pilot bushing $25
-Shifter boot $Crown Royal bag

We already have a spec stage 2 clutch cover, aluminum flywheel for added lightness, and and OEM clutch disc. Just need a Cherokee 5-speed pedal assembly and we're golden. At least that's how it looks on paper. We have until December to get it all done and sorted out.

LSxJ Cherokee kicking ass on a road course, 139 mph top speed

The good news is the Jeep was incredibly (fast when it was running) at our last race, among the fastest cars on track. Should be exciting with the new tranny, wish us luck!

-Matt

 

[R.DesJardin]

4L60E huh???

 

[IXNAYXJ]

4L60E huh???

Nope.

 

[cal]

What was the physical failure like?

Ultra4 has been asking us to put a scatter shield above our aw4 "because they always fail explosively". I've been trying to find one that failed explosively..

 

[souske]

So you are keeping the van motor, or swapping in an ls?

Either way, the t56 ifs a good trans.

 

[IXNAYXJ]

What was the physical failure like?

Ultra4 has been asking us to put a scatter shield above our aw4 "because they always fail explosively". I've been trying to find one that failed explosively..

Did you watch the video? It was just went boom.

Haven't pulled it out yet, obviously I'll update when I do.

 

[IXNAYXJ]

So you are keeping the van motor, or swapping in an ls?

Either way, the t56 ifs a good trans.

We were given an LQ4 6.0 out of a 1-ton van after the 5.3 took a crap...but we try to downplay the nearly 400 lb/ft of torque (after the ECU tune). That would make it one of the most powerful engines in LeMons. Since its visually identical, we're calling it an LR4 4.8 liter.

 

[hubs97xj]

So, basically, America's next supercar is going to be a 25 year old station wagon built from wrecks and spares and sponsored parts?

 

[IXNAYXJ]

Haha, maybe. The guy in the 997 C4S I passed during an open track day didn't find it amusing, though.

 

[kastein]

Might not want to post that publically if you are downplaying it...

I ain't saying shit, but all it takes is one tattletale and shit's wide open.

Too bad about not being able to hold the required tolerances, can't wait to see how it does with the t56. Wouldn't be surprised if you honestly got it for $0 after parting the donor, I got an nv4500 ($1000+ on carpart) for $270 after parting out a dodge, and all I sold was the axles, plow, scrapmetal, and fuel in the tank. And I missed out on a few hundred in interior stuff I didn't feel like dealing with and the tranny came with a free engine and tcase bolted to it Hell, how much did you make parting the donor?

 

[IXNAYXJ]

Might not want to post that publically if you are downplaying it...

I ain't saying shit, but all it takes is one tattletale and shit's wide open.

Well, at the end of the day they're all pretty much the same much the same motor, and with tuning and a cam you can build the same power out of any of the three in the family (4.8, 5.3, 6.0). Ours is is totally stock (and we really did get it for free, guy thought it had a blown head gasket/warped head, but it was just a leaking water pump) except for the ECU flash telling it not to freak out about anti-theft, etc. And besides, cheating is semi-encouraged. Not to mention it's still a 3k pound SUV with solid axles racing against BWWs, Porsches, Mustangs, etc.

Hell, how much did you make parting the donor?

We came out a little ahead, but the car was in pretty bad wreck. We sold the LS1 and interior and kept the tranny. I think after our expenses in towing it around then chopping it up and getting to the crusher we might have paid for our beer while we were working on it.

-M

 

[Johnnie Walker]

I think you will very much enjoy having the LSx/T-56. Am bummed about the AW4 adapter. Altho, I'm sure given the time and being able to create within spec'd tolerances would work just fine.

 

[IXNAYXJ]

Ok...finally got around to pulling the AW4 and found out that the transmission itself wasn't the failure. It actually ripped the flex plate apart and broke the snout off the torque converter. Pretty crazy:

But after screwing around with the adapter and AW4 for over a year, we've decided to throw the baby out with the bathwater and move on. Plasma cutter made a hole for our new shifter in no time.

We were able to reuse the stock x-member, all we had to do was add a 2x2 piece of box tube to mount it to the factory trans mount. Lined up amazingly well (angle is just there to support while attaching our "adapter").

And voila! 6-speed Cherokee.

What's amazing to us is how easily it went together. AND, we couldn't believe that the factory 2WD driveshaft was almost the perfect length. Not quite as much spline engagement as I'd like, but it's acceptable. That's about the last piece of Jeep in the drive train anymore.

-Matt

 

[IXNAYXJ]

We're using the stock F-body clutch, etc, all we had to do was find a generic clutch master cylinder (Cherokee one has a goofy fitting on it) from a Ford F-250 and had a custom clutch line made. Pedal feel is great, engagement is right where it should be. I couldn't believe how easy it is to drive at low speeds, feels OEM.

And of course, obligatory burnout video:

https://www.youtube.com/watch?v=67gVxA_t0L4

-Matt

 

[Root Moose]

So the shifter comes up more or less in the factory hole in the tunnel?

 

[IXNAYXJ]

It's about 4" aft. We just enlarged the factory opening.

 

[Root Moose]

Is that in the most forward opening in the top of the transmission?

Sorry for being "question boy".

 

[IXNAYXJ]

Is that in the most forward opening in the top of the transmission?

In the top of the transmission?

 

[Root Moose]

Yeah, IIRC you can move the shifter from the rear most position to the inspection cover location or depending on which T56 you have there will be another location in between as well.

 

[IXNAYXJ]

Yeah, IIRC you can move the shifter from the rear most position to the inspection cover location or depending on which T56 you have there will be another location in between as well.

My shifter comes out of the rear most cover; came out of a LS-equipped Trans-Am. I think it's got the factory SLP short shift kit, which is nice. Shift action is nice and direct.