Daily Driver JKU on Tons

[pvkj454]

The Jeep is running and driving now. The tune supplied by RPM Extreme worked great and only required tweaking the MAF cal to match my air intake. The 4.10 gears are great on the highway but 4.56 would be a better match for the 37s. Not worth the trouble to swap. I have the JK fan temporarily cobbled to the 392 radiator while I am waiting on the 392 fan that is still on backorder. I am going to add an engine oil cooler and a power steering cooler.

I am still working on two issues. The fuel gauge and the A/C button stopped working. They both run through the canbus system which is working correctly. The gauge cluster sends out the A/C request signal by design but that isn't happening. Scan tool reads the fuel percentage correctly, turns on the A/C led and compressor. This is all on the Jeep side and not the GM side. The TIPM and cluster have both been replaced.

 

[gt1guy]

Is that DEI exhaust wrap or another brand?

How well does it work?

 

[SLOWPOKE693]

Is that DEI exhaust wrap or another brand?

How well does it work?

I used the DEI wrap on the header for my SxS and didn't have much issue. Only minor problem I had was hitting it with the power washer tended to mess up the weave and make it look like shit.

 

[pvkj454]

Is that DEI exhaust wrap or another brand?

How well does it work?

It is from Amazon and 100' is $30. Some of the exhaust is double wrapped. It seems to help but I have only put my hands near it and never checked the temperature difference.

 

[pvkj454]

I posted earlier that the A/C button and fuel gauge were not working. The TIPM was not communicating correctly with the cluster. Scan tool read fuel % and turned on A/C. New Mopar fuel pump unit when the body was off for the LS swap. Checked wiring and eventually replaced TIPM, cluster, evap temperature sensor, and HVAC controller. I sent the new TIPM to Jon and he verified that it was working correctly. I re-installed the original cluster since it was not the issue. I fixed it by changing the Roll Counter Ignition Cycle Reset from 16 to 3 with JScan then they both started working. I don't understand why this worked since I had reset everything using JScan before.

Still waiting on the 392 cooling fan and Mopar keeps changing the ship date. I am tempted to have an aluminum shroud built for the Camaro fan.

 

[gt1guy]

What is the roll counter ignition cycle reset? What does it do?

I've honestly never heard of that before.

 

[pvkj454]

What is the roll counter ignition cycle reset? What does it do?

I've honestly never heard of that before.

The exact terminology in JScan is Rolls Mode Ignition Cycle Counter. Description is Number of ignition cycles required to restore normal vehicle operation. It is in the TIPM section in JScan. It doesn't make a lot of sense but it must try to restore communication after a certain number of ignition key cycles.

 

[pvkj454]

I finally received the 392 fan that had been ordered for months and installed it. That thing can move some air. It is rated at 850 watts so I used an 80 amp resettable circuit breaker.

 

[pvkj454]

 

[pvkj454]

I have ben daily driving the Jeep with no issues other than the spongy brakes. I haven't seen a good fix for one ton brakes while keeping ABS. I just had my third J8 master cylinder to fail. It lasted around a year with the other two failing shortly after install. The J8 master cylinders are junk. I tried the later model 1 1/16" JK M/C also but the brakes were very spongy.

There is not much room for a longer M/C booster combo unless you move or eliminate the ABS actuator. A 2002 Dodge 2500 van M/C is 1 1/4" diameter but short like the JK M/C. The dual diaphragm van booster is longer and has a different firewall bolt pattern. I finally ended up modifying the van M/C and J8 booster. My brakes work great after this and are not spongy at all.

I elongated the mounting holes with a die grinder and a 5/16 drill bit.

The J8 booster doesn't have an adjustable pushrod so I depressed the booster with a ratchet strap and broke the tip off of the pushrod. It has a hole in the pushrod around 3/4" deep which I drilled and tapped to 1/4" fine thread. I cut the head off of a 2" long grade 8 bolt and kept removing a little at a time and rounding the end until the M/C fit correctly without depressing the plunger.

The M/C uses one M12x1.0 and one M10x1.0 fitting and the ABS actuator uses two M12x1.0 fittings. I adapted to 3an and used 12" long braided line with a 90 degree on one end. I had to trim the fluid level sensor connector so that it would fit.

 

[gt1guy]

Very cool solution you came up with for the pushrod.