Smoke,
Welcome to the world of CRD KJ's. Here is a breakdown on the F37:
In stock form, when first released, CRD Liberties produced enough torque to overcome the dampener ability of the stock torque converter used in the 545RFE trans. (the same as behind Hemi engines) This caused shudder of the driveline, and detonated a few TC's. The F37 was instituted as a "fix" for longevity; the orders given to dealers were to flash the Jeep, which detuned the engine and changed the shift points on the TCM. Part of that recall was to replace the torque converter with a newer unit, if the dealer deemed it necessary. (If the tech could demonstrate shudder/ trans problems - see below)
Somewhere in this time frame, there was also a recall for the transmission pump - not sure which recall/ Technical Service Bulletin (TSB) this was.
The reflash of the TCM raised the 5th lockup shift point to a higher speed. Non-F37 TCM's shift at 57 mph via GPS, or about 53/ 54 mph via the speedo with stock tires. (For some reason, stock, the speedo is off about 4 mph in all CRD's) The F37 flash raised it to 61 mph via GPS or 57 mph via the speedo with stock tires. It is extremely irritating on 55mph highways, since you have to speed up to at least 61 mph, let it lockup, and then slow down to about 57 to maintain lockup. It will downshift at 56 mph to 4th lockup. (#'s via GPS)
In 11/2005, Chrysler changed over to a new style of torque converter that was less prone to failure, so all CRD's with a build date of 12/2005 or later have that TC from the factory. (Check the build sticker on the jamb of the driver's door for the build date) Any built before that, if the owner could demonstrate shudder, would have the TC replaced as a part of the F37 recall. However, F37 was not instituted till after all US delivery CRD's were manufactured, so an owner had to bring in their CRD for the flash. Therefore it is possible to find (though rare) an 06 CRD with a 12/2005 or later build date that has not had the F37 detune performed. Some even had TC replacements, had the engine detuned, but for some reason retained the old shift points. (I think UFO has one like this)
Things to check on your potential CRD are:
1.) Shift points under moderate acceleration (to determine if it has had F37).
2.) Getting the TC to lock up in 5th then applying steady pedal pressure to increase torque in lockup to see if it will shudder - best done on a grade if possible.
3.) Squeeze/ handle the boost hoses running to/ from the intercooler to see if there is oil soaked through from the CCV vent. Oil will degrade these hoses over time and leave you stranded when they burst.
4.) Check its history on EGR valve/ FCV valve replacement. (another common problem)
If you decide to purchase, I strongly suggest a Green Diesel Engineering ECO-Tune or HOT Tune. This will restore the engine's torque that the F37 detune took away, and negate the problems you might experience with the EGR valve. There are other routes you can go, too, (SEGR, InMotion Tuning) but this is one of the most common.
Here is a link to a thread that goes into the EGR and CCV in more detail:
viewtopic.php?f=5&t=50930&p=581796#p581796As far as mechanical upgrades like many do to the Cummins, you are limited by the physical properties of the engine. This engine has an aluminum head, and if you overdo the addition of fuel and boost, you will blow it. GDE and InMotion both tune the engine via ECU mapping to work to it's utmost within the physical limitations that it has.
If you do decide to upgrade injectors, add chip or "fooler" boxes, just keep in mind that it is well-nigh impossible to find a mechanic that knows anything about these engines. Most Jeep techs would even be surprised, saying "I didn't know these came with a diesel. . . ?" That is why this board is what it is - we are our own Jeep diesel service techs.
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In this war of lines, so many have been crossed. Where will it all stop?
2006 Deep Beryl Green CRD Sport
*SOLD 1/22/12*Provent, V6 Airbox, Fumoto, Samcos, GDE ECO & TCM Tune, Euro JK TC, Magnaflow Catback
245/70/16 Destination A/T's
Boiler's Radiator Skid PlateJeepin' By Al 2.5 inch Adjust-A-Strut Lift, JBA Gen 4.5 UCA's (6/5/10)
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Also it looks as if the suncoast it just way over built...whcih can be a good thing. But the difference in price is the only issue. If the Euro will hold the power for half the cost, great! But i know the suncoast should last forever. Its a tough one for sure...i will have to do more research for sure.
it will raise my blood pressure lol, but yea...this thing had been smashed and was nothing like the pics online. we came ready to buy it but......red clay was caked under the body, huge dents under the body and on skid plate, turbo seals were leaking oil, rear diff pinion seal leaking, intercooler hoses saturated with oil, sun visor broken, cup holder cover missing, no manual,rotors warped, tires w/ only say...30% left, and transfer case leaking...oh and it had the flash. So with that being said despite the damage i offered them $10k and things got ugly so we left....they didnt even try to stop us or counter offer. but anyways. Lesson learned...i could keep going on and on but i really dont want to get mad. leaast they could have done was clean it. At any rate we did like the power and the wide field of veiw. It felt good to drive. We will deff be get'n one asap. Found one in KY..let you guys know how that goes 