Hello, Brent:
The mileage you get varies depending upon a lot of factors. Are you going to perform all of the PROPER upgrades to this engine? Are you getting a lift done? All said, a CRD engine will net you better fuel economy than the gasser if the proper upgrades are done and all other factors between the two vehicles are the same.
The following are the upgrades I recommend for ALL CRD engines. There is more you can do to get substantially more power, but these upgrades are not going to hurt your engine like some of the poorly thought-out upgrades by some of the online "experts". The following information is an abridged version of the full article I wrote almost 2 years ago. If you want the full article that explains in detail WHY these upgrades are necessary, please e-mail me at
[email protected].
"HERE ARE MY TOP 6 CRD ENGINE UPGRADES FOR THE NORTH AMERICAN MARKET... THIS IS OUTSIDE OF ANY SPECIFIC ISSUES YOU HAVE WITH YOUR OWN ENGINE, AND APPLIES TO ALL CRD ENGINES GENERALLY....
I have recently been getting a lot of questions from CRD owners regarding proper upgrades to the CRD engine. As a Jeep Liberty CRD owner you should know that this vehicle is saddled with a lot of problems; 50% of which are pollution control related. 30% of the problems are due to owners using cheap and short-sighted “upgrades” to fix the pollution control problems and other CRD engine problems, along with unwise operation and driving practices. The final 20% are caused by Daimler Chrysler's penny-pinching and planned obsolescence for this vehicle. To counter a lot of these problems, the following are my 6 recommended upgrades for the CRD engine.
Be sure to consider quality choices for each of the upgrades as there are alternatives that can cause problems down the road. The Liberty CRD responds well to the use of quality parts and upgrades; cheap versions of upgrades and cutting corners are bad ideas with this vehicle. Please consider all of these upgrades if you are intending to keep your vehicle a long time. Perhaps you are a second, third or 4th owner of your CRD; if this is the case some of these items may already be installed on your CRD...
1) An engine and transmission tune through reprogramming the engine and transmission computers. The best tunes cut out the pollution control system through the computer and re-tune the engine for maximum efficiency. I personally like Green Diesel Engineering tunes the best.
2) A hotter engine thermostat assembly, (really, the only choice is a HDS Model 001 thermostat assembly).
3) An in-tank fuel lift pump, (Airtex E7181M or equivalent). Liberty CRD vehicles in North America never got an in-tank lift pump; I am unsure if the Cherokee CRD vehicles in all other markets around the world have factory in-tank lift pumps.
4) A Webasto TSL17, (also known as a Thermo Top C), engine coolant heater. Get the 923369 universal installation kit and install it at the same time as you install the fuel lift pump because you have to drop the fuel tank for both installations. Follow up with the purchase of the upgrade battery tray from Sasquatch Parts that allows you to install the Webasto heater underneath.
5) A Provent 200 kit from Sasquatch Parts, including their special bracket and custom hoses... not cheap, but VERY nice!
6) Physically cut off the ability of the EGR system to operate. This does not mean remove the EGR valve completely; simply remove the tube running from the exhaust manifold to the EGR valve and install a 1-way check valve in the EGR valve to allow it to continue to be used as a turbo-blow-off valve."
FYI, Brent: There is a fellow in Boise who has a substantial collection of Liberty CRD vehicles and parts. You are not far away from this fellow, so sourcing hard-to-get parts should not be so difficult for you. I am trying to check with him to see if he still has his inventory.