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Messages posted by: GreenDieselEngineering
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The TCU uses several different signals together to determine the shift points.

Vehicle speed does not seem to be a critical factor, at least changing the revs/mi in the cluster did not have any effects. There are other internal checks in the TCM that are limiting the shift points.
Yesterday after driving our 06 with new red top, the voltage after shutdown was 12.8 V (warm battery). This morning the voltage (with key off) read 12.3 V. The readings vary wildly depending on the conditions.

We also measured the current draw inherent with the vehicles after sitting overnight. Both the 05 and 06 measured almost 1.7 amps of current across the terminals, not sure how this compares with other vehicles yet. Most vehicles have some sort of leak rate for current, usually low enough to be able to start the vehicle after a few weeks of sitting (in a perfect world).
It is a 150k factor converter based on our information. Not sure what that equates for the stall speed, but it is the same as production.
We have successfully translated the glow calibration from the latest release and installed it on all the tunes we offer. With this, no matter what ECU part number one has, with the tune the glow plugs will be operating at the safest temperature (as best as it can be). This will help to ease worrys about glow plugs for customers with older vehicles looking for an update.

We did our best to prevent shudder initiation with the ECO tune by limiting the amount of torque available between 1650-2100 rpm. We were not able to get shudder even when pulling a trailer, the transmission would hit the 'unlock' region before the shudder started. This was accomplished with the F37 traditional damper converter. The ECO tune has not eliminated all shudder in every customers vehicle. There is just too much variability in the amount of torque the stock converter can safely handle and if you already have shudder the ECO tune will most likely still produce enough torque to cause shudder, there is no fix for a weak TC. The HOT tune and turbo kit both cause massive amounts of shudder with stock converters...this is the main reason we opted to update both our vehicles with the new Mopar unit.

It might be nice to experiment with different k-factors, but the Mopar unit is not very far off base, as the stall speed changes so does the multiplication factor. The k-factor is a trade off for fuel economy (less slip) in light load driving and having the rpm in the best band during heavy load driving. Keep in mind, the new Mopar unit is used on all the new Jeep diesel products sold overseas and these engines have more power. The best part of the new converter is the higher spring capacity in the lock-up clutch as this is the problem source with the current TC in the KJ. We understand your concern and it is rightly based, but the new TC is a big step in the right direction.

Best of luck!

We measured the voltage during the first second of "key-on" before starting a cold engine. There is some draw from the glow plugs during this period. Today with the new optima red top we measured 11.2 V and the engine started in 1.35 seconds. The battery voltage seemed to have a strong positive effect.

12.1 V is not a bad number with no loads, try measuring it with a load from the glow plugs in the morning. A failing battery will have a larger voltage drop, ours was down in the 10s V.

We trickle charged it for 10 hours and measured voltages around 11.7 V, then after three days of sitting the voltage would drop to about 10.7 V.

Here is a rundown on the 06 with new battery voltage measured at the terminals from this evening after sitting all day at 55 F.

key off 12.17 V
key on 11.75 V during glow phase, steadies out after several seconds at 12.05 V
cranking 9.70 V lowest visibly seen on hand held meter
running 14.30 V
shutdown 12.50 V trickled down to 12.2 V after 30 seconds

Colder temps will drop all these numbers. We have seen cranking voltages drop down in the 7s at -15 F.

The optima has very high power density. A good battery for this application. It would be interesting to know how many people with failed batteries ever charged their battery for any reason? The gel batteries require a specific charger designed to charge in a specific manner to promote battery life. We only have a regular/deep cell charger and have a feeling this contributed to the demise of the battery. Time to go shopping for a new charger...
We have not tested other starters, but there are several on the market that would provide faster cranking speeds. It would be important to make sure the pinion is matched for the flywheel and the alignment is correct. We are not aware of any off-the-shelf starters for the KJ and some manufacturer design work might be necessary.

During our cold start tests the last few days, we have noticed significant variance in start times based on battery voltage. The red top in our 06 is starting to go...fast. With the coolant temps around 5 C the 2006 KJ started in 2.35 seconds and the battery voltage was at 10.7V. In the 2005 KJ the start only took 1.0 seconds and the battery voltage was at 11.2V. The lower system voltage affects the glow plug temperatures and the voltage supplied to the injectors. This reduces the engine's ability to have optimized combustion. Once the engines started and the alternators kicked in, the voltage on both vehicles stabilized at roughly the same point. We are replacing the battery today in our 06 KJ and will post results in a few days.
Good questions. The fuel economy drop in the winter can drop significantly in the winter. We see a general decrease around 10%, but this can vary based on conditions. The fuel tends to be the largest factor. You might see an additional 5% drop if the vehicle is strictly a commuter due to having a cold start in the morning and a cold start returning home. The cold oil requires a few minutes to warm up. The lighter viscousity 0-W40 oil helps reduce the FE drop.

We are noticing that with the tune the warm-up is quicker with decent heat in cabin in about a 1/2 mile of city driving. The advanced timing helps transfer more heat to the coolant, should be directionally correct for improving the FE.

Fuel temps can effect efficiency, but it is usually not a big factor. Temps in the range of 30C to 50C at the engine fuel inlet are optimium, colder temps may have slightly more ignition delay and this will tend to drop the fuel economy. With the tune, the higher injeciton pressures help to increase the fuel temps in the common rail and minimize the ignition delay. The pressurizing of fuel in the rail can add between 30-70 C to the inlet fuel temps. The return fuel temps are also slightly higher to help warm the fuel in the tank faster.

The fuel heater has minimal impact on increasing the system temps. The injection system heat load is at least 100 times greater and probably more. We will instrument one of our KJs to see the temperature difference across the fuel heater and the return line to the tank. After a few weeks of monitoring we should have some hard numbers for you.
We are still going strong with the new torque converter offered through Mopar. It is a marked improvement over the stock units.

We have been testing it with our stage II turbo kit and the power delivery is phenomenal with the transmission in lock-up. At this point we are recommending the converter to all CRD owners that want to rid themselves of "shudder". It makes us shudder just thinking about failing a stock converter pulling a trailer up a mountain! It is well worth the cost to upgrade.
It is a known issue that the ceramic glow plugs have longevity issues in the KJ CRD. The plugs used in these vehicles were 1st generation and are prone to failure from overheating and other internal design issues. There are several different ECU releases during the two model years and if your vehicle is not running a fairly new release then the glow plugs could be more as risk of failure. To date our tunes have focused on fuel economy, drive ability and performance. We are now starting to review the glow calibration and will be including the most up to date release in all our tunes regardless of the ECU firmware level.

We have successfully translated the glow logic from the latest firmware to the older version and tested it on a 2005 vehicle. The next step is to do the same with a 2006 vehicle and then perform daily validation with the cooler temps to verify the functionality. The goal is to have new tunes available by 21 October.

Additionally, we are planning to lengthen the time the glow lamp is illuminated on the dash. We are only planning to add about 0.5 seconds to the light. This will help remind customers to delay cranking the engine in cold conditions to give the glow plugs adequate time to warm-up.
There is another factor that makes the Jeep take a little longer to start when compared to the older VWs. The KJ is a common rail engine and the first 2-3 engine revolutions are used to fill the rail with fuel and pressurize it to the proper pressure. During this time, the injection is not yet even activated. The older VW had unit injectors that are capable to fire immediately.

The tune added the rpm flare right after the start to assist with a stable idle and to help build vacuum slightly quicker than the stock calibration.
Good question. We have noticed this on both of our vehicles as well. In warm conditions the start is very quick, then in the range of 40-50 F the crank times are about 3 seconds. As the temps get lower, the starts begin to improve again. We saw 1-2 seconds at 30 F a few days ago. The temperature range you are having issues with is when the glow plugs stop having pre glow or it is so short the glow light barely flickers. We have not modified the glow calibration yet, but the longer crank times in mid-ambient temps may justify seeing if we can have the glow plugs on for a second or so to get some heat in the chamber. With a cool engine block the start ability is not the best without any preheating of the glow plugs. Let us know how the start times change with varying temps as the winter rolls in...it should improve.

The other issue with the KJ CRD when comparing to other diesels on the market relates to the starter and cranking speeds. The gearing and torque of the starter is only producing cranking speeds of about 105-110 rpm in very cold conditions. Other products will have cranking speeds of 120-140 rpm in the same condition. This difference in speed is huge when we want to compress the air in the chamber. The faster the cranking speeds, the more heat build-up due to compression and less leakage past the rings.

If anyone else has noticed this or other variance in cranking times, please let us know.
We have shipped to Canada. The shipping time takes a day or two longer depending on your location and we have to fill out a couple customs forms, but generally it is not a big deal. We use USPS for all our shipping due to only having a PO box at this time. The cost for the product remains the same.
Torque Converter Replacement Pointers

1. Disconnect battery.
2. Make sure vehicle is secured on a lift or up at least 10 inches on jack stands.
3. A tranny jack is a must for supporting the trans after disconnecting from engine.
4. Remove mechanical fan with a large crescent wrench or equivalent. May need to hold the fan hub pulley in place while hitting the wrench with a hammer, it is a standard thread so left to loosen.
5. Remove wiring from starter and remove starter (3 bolts).
6. Remove torque converter access plug, located just above starter.
7. Remove front skid plate (4 bolts).
8. Pull transmission line connector off the attachment stud on the bottom side of oil pan. This provides enough play so trans cooler lines do not have to be disconnected.
9. Remove front propshaft (NOTE: use paint pen to mark both shafts when removing so they are re-installed in same orientation this will make sure the balance is maintained), may need to use a punch to pop out CV joint after bolts are loose as it tends to freeze in position. Having the trans in neutral may make disassembly easier.
10. Remove 4 bolts holding rear driveshaft to axle, let the drive shaft hang down.
11. Disconnect the two exhaust hanger isolators from the crossmember.
12. The front hub on the engine has a 20-21mm nut that is used to rotate the engine over clockwise to get the 4 torque converter bolts to line up in the access window just above the starter.
13. Line up each TC bolt in window and remove one at a time, then rotate engine 90 degrees and proceed with next bolt until all four are removed.
14. Remove all the bolts holding the transmission to the engine, minus the two that are on the topside of the trans.
15. Remove the six crossmember bolts, while having a jack supporting the transmission.
16. Lower the transmission as far as it will go, now you will have access to the two bolts at the top of the trans that are still holding it to the engine (keep slight pressure on the jack).
17. Use a swivel and long extension to reach the two bolts from underneath the vehicle, the approach should be from the driver’s side of the vehicle.
18. Jack up tranny a little bit and then pull the unit rearward until it disconnects from engine.
19. Disconnect the 10mm bolt that holds the transmission dipstick to the trans. Pull the dipstick upward until it pops out of tranny (may need to lower tranny for this).
20. Now the unit can be lowered and pushed further back so the torque converter can be removed.
21. Make sure have a drip pan underneath bell housing when removing converter as 1 to 3 quarts of fluid will drain out of converter.
22. Re-install in reverse order, make sure to align the dowel pins on the engine adapter plate to the bell housing and tighten one attachment bolt to pull the units back together.
23. Note when installing the four bolts that hold the torque converter to the flywheel. Get all 4 bolts installed one at a time, but just hand tighten and back out ¼ turn until all four are installed. Then torque each one and finally complete a torque check on each bolt after the sequence is complete. There is no sense to short cut this and risk a torque converter becoming loose.

The process takes about 6 hours for an experienced mechanic, budget 2-3 hours more for the weekend warrior.
At this time we have put about 1500 miles on one of the European converters and no issues to report. The trailer towing was uneventful, typically a good thing with us! No shudder present, however the driveline vibration can be a bit higher due to allowing higher torque in lock-up conditions. The energy amplitude transmitted through the powertrain mount system is higher, but in the end it is a Jeep. We prefer capability over refinement in ride quality from an NVH (noise, vibration, harshness) standpoint. The flogging will continue!
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