Jeep LS swap for the LJ

glockman

I hate Jeep trucks
Location
Pleasant Grove
While I was installing the shifter I decided to address the 4low issue.
The GM PCM needs a ground signal on pin 16 of the C2 connector when the T-case is in low. This enables a different shift table so it shifts correctly. I had the harness screwed up originally and that caused terrible performance.
I thought the T case range selector switch was bad so I scavenged 3 more from the junk yard. The switch is just a two wire on/off contact.
Turns out mine was good, but the OEM switch closes in 4Hi or 4Lo so it's a no go unless I pull the case apart and grind the 4Hi portion down until it doesn't close the switch.
For now, I wired a switch under the T case handle that will send a ground signal to the PCM.
 

glockman

I hate Jeep trucks
Location
Pleasant Grove
Good news. The leak is gone.
Bad news, once it was buttoned up, it had a loud clunking noise under any load. Wtf?
Ran it in 4wd with no rear driveline and the clunk is gone.
I ran through a few possibilities and got some info from @Gravy.
I'm thinking the chain is stretched and I have the wrong shift fork pads. The teeth on the synchro gear are a little chewed up.

20201110_114948.jpg
There was also a bit of aluminum inside the syncro slide.
20201120_155026.jpg

So I ordered a new 36 link 1.25" wide chain, shift fork pads and all the bearings that weren't replaced with the SYE kit.
Hopefully this gets rid of the clunk and the faint squeal it's had since the swap.

I also fixed the range selector issue while it's apart. Now it only closes the switch in low.
20201110_172152.jpg
 

glockman

I hate Jeep trucks
Location
Pleasant Grove
New chain and every bearing in the Tcase and its still clunking. I've gone through everything I can think of. I'm at a loss, especially due to the situation that it started, by simply removing and reinstalling the Tcase. So imma drive it till something grenades and then I'll know what it was.

Pulled the Tcase for one last time. The seal on the transmission side was leaking. This time I used a gasket that came in the rebuild kit. We'll see how it works.

In unrelated news, I have had issues with the oil pan I chose. The C6 vette pan I have has a pickup in the middle of the pan instead of the rear. I started losing oil pressure with the front end 20" above the rear.
I recently found poor man motorsports makes a retrofit pan that is the same depth, and has a trap door baffle for $300. Most other brands are selling the baffle for $200. So picked one up and got it installed yesterday.
The kit came with a new pickup, gasket and all new bolts.
Screenshot_20201216-084417_Chrome.jpg
20201215_155228.jpg
 

glockman

I hate Jeep trucks
Location
Pleasant Grove
Or even a control arm joint on the rear.
The CV joints are brand new on both drive shafts. I have removed them individually and it only makes the sound in 2wd, which rules out the front. I have rebuilt and lubed the control arms when the motor went in and drove it a couple thousand miles since with no sound until I removed the T-case and installed the Lokar shifter. I thought it might be the shifter not engaging properly so I remove the cable and move it to drive at the sector shaft and same sound.

I'll post some video.
 

glockman

I hate Jeep trucks
Location
Pleasant Grove
So I've put a thousand miles on it now. I think the clicking noise may be the RCV's. They were in it when I bought it with 35k miles on it and its now at 111k. I replaced the passenger side outer due to my incompetence cross threading the spindle nut around 75k.
I think the drivers side is worn out and causing the noise. I'll order a rebuild this week and see if that solves it.

I am also unsure I'll keep the Lokar shifter. It works fine and the issue of not knowing what gear its in hasn't been an issue for me. I am going to try and cut an extra gate in the factory shifter and see if that works. The look and feel of the stock shifter is just superior and it requires less modification to the console, almost like it was designed to fit together :rofl:

My registration is due this month so I'll see how I fare getting it past UT county emissions.
 
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SnwMnkys

Registered User
Location
Orem, Utah
My registration is due this month so I'll see how I fare getting it past UT county emissions.

Take it to Daves Canyon Auto on 8th and Main in Orem. I needed Emissions done on my LS powered JK to get it to pass he would hook it up and tell me if it was a go or no go and not outright fail me. Then he pointed me in the right direction as far as what I needed to do.

Does your ECU VIN match the Jeep VIN?
 
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glockman

I hate Jeep trucks
Location
Pleasant Grove
Take it to Daves Canyon Auto on 8th and Main in Orem. I needed Emissions done on my LS powered JK to get it to pass he would hook it up and tell me if it was a go or no go and not outright fail me. Then he pointed me in the right direction as far as what I needed to do.

Does your ECU VIN match the Jeep VIN?
The VIN doesn't match. I am not aware of a tool that can program the GM ECU with the Jeep VIN. I have been told HP Tuners doesn't have that functionality. Do you know of one? That would be the easiest solution.

I have a guy that will let me know if it fails without failing me.
When I called the county emissions in Spanish Fork they said it has to be inspected by them, then they change something on their side to show it has a different engine so any emissions station can plug into the OBD port an pass it.
 

Greg

Make RME Rockcrawling Again!
Admin
Take it to Daves Canyon Auto on 8th and Main in Orem. I needed Emissions done on my LS powered JK to get it to pass he would hook it up and tell me if it was a go or no go and not outright fail me. Then he pointed me in the right direction as far as what I needed to do.

Does your ECU VIN match the Jeep VIN?

Man, I used to work there... around '95-96? Wonder if Dave still owns & runs the place?
 

Bart

Registered User
Location
Arm Utah
The last time I checked you needed a certificate from the County before it could be inspected. Please let us know how this goes.
 

SnwMnkys

Registered User
Location
Orem, Utah
The VIN doesn't match. I am not aware of a tool that can program the GM ECU with the Jeep VIN. I have been told HP Tuners doesn't have that functionality. Do you know of one? That would be the easiest solution.

I have a guy that will let me know if it fails without failing me.
When I called the county emissions in Spanish Fork they said it has to be inspected by them, then they change something on their side to show it has a different engine so any emissions station can plug into the OBD port an pass it.

EFI live does it. Thats what I used. It may pop a red flag without matching VINs. The tech said he wasnt sure. He said to take it to the main Emissions center for Utah County in Spanish Fork. But I just went ahead and bit the bullet and ordered an EFI Live package since I wanted to do tuning anyway.
 
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RockChucker

Well-Known Member
Location
Highland
When I had to get mine inspected in SL county, I always had to take it to the salt lake valley health department in Murray because of the vin mismatch issue. And they crawled over it every year making sure all the emissions stuff was hooked up correctly
 

glockman

I hate Jeep trucks
Location
Pleasant Grove
There was a guy on LS Swapped Wranglers working on a stand alone tuner for VIN programming. I'll have to do some research. Going to the county every year would be a nightmare.

Edit:
Just called UT county emissions for the 3rd time since starting this swap and got another different answer.
Today they said to just take it anywhere that does emissions testing and they can handle the VIN mismatch.
I take all my stuff to Jerry at Johns towing in AF because he is such a nice guy and I think really needs the money. We'll see if he can actually do it.
 
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zmotorsports

Hardcore Gearhead
Vendor
Location
West Haven, UT
The VIN doesn't match. I am not aware of a tool that can program the GM ECU with the Jeep VIN. I have been told HP Tuners doesn't have that functionality. Do you know of one? That would be the easiest solution.

I have a guy that will let me know if it fails without failing me.
When I called the county emissions in Spanish Fork they said it has to be inspected by them, then they change something on their side to show it has a different engine so any emissions station can plug into the OBD port an pass it.

When I had to get mine inspected in SL county, I always had to take it to the salt lake valley health department in Murray because of the vin mismatch issue. And they crawled over it every year making sure all the emissions stuff was hooked up correctly

To my knowledge no aftermarket tuners can change or alter the VCN in the ECM/TCM.

I did what RockChucker did and I took mine to the Utah Board of Air Quality in Salt Lake (Murray I believe) and they did a complete inspection to ensure all emissions equipment from the donor vehicle were installed then ran a diagnostic test to check for VCN (Vehicle Calibration Number) and lastly plugged in to ensure all readiness monitors were set and no issues reporting back to the ECM. Basically they go through to ensure it is 100% USEPA compliant, then they changed the state's record to show that my Jeep is actually a 6.2 liter drivetrain with the GM VIN# attached to the Jeep's registration. Each year after that I merely take it to any emissions testing station and when they scan the VIN # they come up with the modifications from the state.

Mike
 

SnwMnkys

Registered User
Location
Orem, Utah
To my knowledge no aftermarket tuners can change or alter the VCN in the ECM/TCM.

I did what RockChucker did and I took mine to the Utah Board of Air Quality in Salt Lake (Murray I believe) and they did a complete inspection to ensure all emissions equipment from the donor vehicle were installed then ran a diagnostic test to check for VCN (Vehicle Calibration Number) and lastly plugged in to ensure all readiness monitors were set and no issues reporting back to the ECM. Basically they go through to ensure it is 100% USEPA compliant, then they changed the state's record to show that my Jeep is actually a 6.2 liter drivetrain with the GM VIN# attached to the Jeep's registration. Each year after that I merely take it to any emissions testing station and when they scan the VIN # they come up with the modifications from the state.

Mike

EFI live changed the VIN in my E38 ECM.
 
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