Green Diesel Engineering

[lanthony2020]

It was suggested over on LostJeeps to post this here.

Recently purchased a 2005 Liberty 2.8L 4x4. 139,000 miles, complete maintenance record, like new in and out. Read all about the transmission problems and EGR stuff. Decided to dive in and go for it! I have wanted an off road diesel for many years.

What did I get: Nice looking and seemingly running machine. Transmission shifted good so I bought off on a Sonnax line pressure kit. Told this would help high mileage Liberty Auto-******. Very simple external plug-in. Results: Not to noticeable, still shifting good. Mileage seemed a bit low. I think 15-21 MPG. Very mixed driving and experimenting.

Had been in contact, with a myriad of questions, with GDE. Finally said OK to the Eco Full-Torque tune and added the towing transmission TCM. I installed the Tune, mechanic installed the TCM. Main mechanic was gone for TCM install so no computer reflash. Thought it would learn. Also had mechanic pull MAP and clean it. It was a solid block of hard soot. He cleaned it up and reinstalled.

Results: Seemed OK but 2nd to 3rd gear shift seems to be like an old "double clutch." It would die and then jerk your neck forward. It was annoying. Called GDE. They recommended a "Quick Learn" on the TCM. Found a mechanic with a Snap-on tablet. We went right through the menus to 2005 Jeep Liberty 2.8L Transmission/ and "Quick Learn" was an actual option. He performed this while I was waiting. The computer started shifting the transmission as he had his foot on the break and wau-lau, he was done. 35 bucks.

Results: Shifting perfectly and now precisely as GDE described for the "Tow" ****** tune. The whole thing really came alive. Really strong on Lone Rock Beach. I really like this thing now.

MPG: Going from Page, AZ to Flagstaff, AZ and back, bucking a side-wind. 600 lbs. on board, just over 32.5 MPG!!! This driving almost all the way at 68 mph. About where the TCM tune goes into 5th gear. Love this setup. Could not be happier.

LN

 

[lanthony2020]

In addition:

I also had added a K&N air filter. My low mileage was in SD when temps were some -20+ F. Running #1 Diesel. My trip to AZ was unremarkable. After filling up in NE, I did manage to pull down 26 MPG through the last storm in the Rocky Mtns. Eisenhower tunnel was closed and it was hours of bumper to bumper. I topped off in Vail as to take me to Moab. Surprised to get only 26 MPG there. I topped off again in Moab, traveling to Page, AZ. Still just 26ish MPG. The "Quick Learn" performed in Page, AZ, really made this take off and I noticed more power and much better shifting in 1-3 gears. 4-5 did not seem to be abnormal.

To get just over 32.5 on my Flagstaff trip. I am so happy, I can hardly believe it. I will be going from Page, AZ to St. George, UT shortly. I will adhere to 68 mph and be conscientious. We will see. I will post.

And the Power in the sand at 24-2600 RPM, WOW! Fantastic torque. If it even starts to bog down, just a little throttle and away she goes. Very impressive. Love this thing.

Now wondering about a 2.5 inch lift from Al's and whatever else?.

LN

 

[lanthony2020]

Page, AZ to St. George, Utah trip. Wanted to check mileage once more. Wind started to blow and was quite challenging both ways.

Took off bike rack. Had cat/muffler removed as it almost fell off. Muffler guy fabricated and install 2.5" pipe (only) through original route. Nice howl and rumble. At about 2500, she takes off like a ***** ape for about 700 rmp. The flow must improve in about this range, I suspect?

Mileage: Very hilly with variable elevations. Small towns and a big run of lights through Hurricane, UT. Total round trip was 306 miles including some city driving in St. George. Filled up at same fuel station, same spot.

Result: 28.6 MPG trying to maintain 68 MPH. I have Toyo Open Country tires. I might be 1-2 MPH off on speedo. Might be tires. Speed trap had me off by two and GDE shift point, off my one. Have not tried to quantify the effect of this until I research further.

LN