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LM4 5.3L and 4L60E swap into 2004 LJ

LBarr2002

LIFETIME
SUPPORTER
We had karate pictures for Nora tonight. Got home at 7:30 and Tripp was already here and had it running right. He printed schematics for both pedals, started troubleshooting, but schematics didnt match up. In a "well, what's the worst that could happen" moment, he plugged the truck pedal into the Buick TAC into the ecu and it works perfectly. We took it for a couple laps around the yard tonight.
 

LBarr2002

LIFETIME
SUPPORTER
Tripp came over last night and tried for a while to get the jeep gauges working. The jeep pcm isnt getting power.

There was also a significant amount of atf under it after our little test drive. It looks like its leaking at one of the adapter surfaces. I was able to tighten a couple of the nuts, but doubt that will stop it. I'll run it a little more and see if I can pinpoint the leak.
 

LBarr2002

LIFETIME
SUPPORTER
Tripp has spent a couple hours a day over several days troubleshooting the jeep pcm and gauges. The pcm is not communicating with the gauges or the obdII connector.

The accuracy of the jeep tach with the emulator, and the oil pressure sensor being more of a dummy light has always been in the back of my head. At this point we're both thinking aftermarket gauges, but I'm open to suggestions.
 

LBarr2002

LIFETIME
SUPPORTER
Burgundy stopped by a marine supply place today and picked up some 5/8 fuel vent line for the large vent on the passenger side of the tank. I ran it across and into the same place as the small vent and made sure it took fuel.

Then I put the front driveshaft in so that I could check clearance and have it in to show the exhaust shop where the exhaust needs to run. I'm still trying to get in touch with my exhaust guy...
 

LBarr2002

LIFETIME
SUPPORTER
As soon as I got home today and ran it out to the hill in the yard and checked clearance. With the left front on the bump stop (soft bump) everything clears. I cant replicate a hard bump full stuff situation in the yard, but I think I'm ok.

I also see the trans leak. The tcase adapter has 2 sets of holes for clocking, and the fluid is coming from the second hole at the bottom stud.
 
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LBarr2002

LIFETIME
SUPPORTER
Random days off are the best. I needed to get by the exhaust shop today so I took the day off. Took Nora to school, went to breakfast with Bennett and Burgundy, came and hooked up the trailer and took the jeep. We have a plan and I ordered a flowmaster 50 delta flow muffler and banks 2.5 inch tailpipe. The jeep will go back to him Tues/Wed for the work.

I also fixed my trailer brake wire that had been rigged since Harlan.

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LBarr2002

LIFETIME
SUPPORTER
I started today with reinstalling the ARB compressor and rearranging my air manifold because the onboard air fitting pointed directly at the ecu. Didn't have to buy any new parts = win.

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I also replaced a broken connector for the coolant temp, and reinstalled the computer.

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I really didn't want to do it today, but my new tcase gasket showed up yesterday so I pulled the case and swapped it out, and used RTV this time.

Then I backed it out and let it run up to temp to verify cooling fan. Then I drove it around the yard a few times and parked it. It's still dry underneath!
 
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LBarr2002

LIFETIME
SUPPORTER
Any semblance of a budget build is out the window. I'm at the point I just want it done and the easiest/quickest/cleanest way to do things is getting done. So... full suite of Autometer Sport Comp II gauges are ordered. I went back and forth on what to use, but decided I wasn't going to skimp on the thing I'll be looking at most, other than the windshield.
 
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