F37 before and after comments...

kjfishman · **Posted:** Sat Dec 23, 2006 9:30 am

Startrng a new thread to keep comments about how the recall impacted us in one spot. than be buried in one of the other threads.

First day back and I think mine shifts better, much firmer. I didn't notice a big difference in shift points. It seems to go into OD a bit earlier and I think that is a good thing. The new TC seems to be an improvement. On the negative side the transmission does seem louder now. I haven't taken any kind of road trip or towed the boat yet to comment on eithor the fuel economy or towing power yet.

oldnavy · **Posted:** Sat Dec 23, 2006 10:37 am

After having the F37 done my first reaction was real inprovement in shifting, but otherwise about the same as before as far as acceleration goes. However I have been driving if fairly regular since wife is out of school for holidays, I have noticed it has almost no lag when throttle is put to the firewall and she really hauls stupid now and will smoke the tires without doing a prestall as had to be done before for quick launch. There is no way to really check mpg gain or loss as we are in the switch over to winter fuel and ULSD fuel, we just need to be patient and see what comes about over the next few months till spring and fuel change over to ULSD and winter blend is over. So far I am pleased with the results and even more inportant, so is the wife.

vtdog · **Joined:** Fri Sep 30, 2005 11:27 am **Posts:** 640

As far as I can tell, no change before/after. The power/acceleration seems the same and shift points are unchanged. I did not have the shudder before the fix and do not have it now. The only change noticed is that the tranny does not clunk when shifting between park and reverse, or drive. MPG appears unchanged as well

macd · **Joined:** Mon Sep 19, 2005 1:46 pm **Posts:** 50

Mine is an 05 and I hadnt had any flashes in at least a year prior to F37. The biggest thing I noticed is I've lost 3 mpg! Before the F37 flash I was getting 24-25mpg all the time. Now I'm lucky to get 21mpg.

I definitely notice a lack of punch. Seems like it revs more now and doesnt have as much snap. Personally, I'd put up with the cluncky shifting to get my mpg and snap back.

tomasnc · **Posted:** Sat Dec 23, 2006 11:17 pm

I echo macd's feelings.

I don't have the power I once had

oldnavy · **Posted:** Sun Dec 24, 2006 12:10 am

tomasnc wrote:

I echo macd's feelings.

I don't have the power I once had

Ours has been done longer then yours? Maybe the the adaptive software hasn't kicked in.

Cowpie1 · **Posted:** Mon Dec 25, 2006 3:37 pm

Recently had the F37 done and took a 400 mile trip with a fair amount of payload. Haven't noticed any change. Had a rare occurence of the "shudder" but have not noticed any on this trip. MPG's stayed the same in the mid 20's even though bucking a 10-20 mph head and cross wind. Shifts seem to feel smooth and firm. Pulls the hills well.

Was a little apprehensive about getting the recall done since not really having any problems. Only complaint was that the Tech did not check the tranny oil level properly and I had to add 3 qts to get it back up to full line. Contacted the dealer and let them know.

blacksmoke · **Posted:** Mon Dec 25, 2006 6:30 pm

Just got back on the forum after 3 months out without my Libby... got it back last Friday with a "transmission reprogram" and the F37 done.
1) Not sure its a lack of power, but the RPM does rev up at every little push on the accelerator. Its strange but I have the feeling the TC is less active, more spinning before actually locking and letting the power flows.
2) Scanguage seems to hold up now, funny it didn't before.
3) Before I left the Jeep to my sister I removed the Predator chip. Tried to put it back this morning put got a code P0652. When I tried to erased the code (while still parked with motor running), heard a big loud "thump", CEL still on: very scary.
I therefore proceeded to power off, remove the chip, erase the code (which worked), restart the engine. Afraid to put the chip back now!!!

I know its not related, but got the darn EGR P0401 now: i was 20K without any problems, now getting close to 47k miles ...

I'm still in Quebec City, returning mid-January in Seattle... miss biodiesel here!
Merry Christmas BTW!

Ripster · **Posted:** Tue Dec 26, 2006 9:29 pm

Had the TQ and pump replaced in mine, shifting is very smooth, they have not been able twice now to get
the F-37 flash to take, could be an omen I guess, just got back from a 1000 mile trip and it was flawless, really
considering not having the flash done. At least till they have a idea why it is not taking.

DnA Diesel · **Posted:** Tue Dec 26, 2006 10:34 pm

Hmmm....wondering about the F37, due to go in tomorrow morning for it, 23 and 18-023-06. So that I don't sound like a numpty in front of the service writer, is 18-023-06 (Flash, "Enhanced TC", Glow plug, SKIM, anti-shudder valve, and brake switch) do I still need this done, or will F37 take care of it all? My gut feel is that -023 is still required...thoughts?

TIA,
Duey

Ripster · **Posted:** Tue Dec 26, 2006 11:11 pm

The F-37 recall paperwork states right on it that the 23-06 is null and replaced by the F-37, read the copy that
was posted here, on one of the F-37 threads and you will know more than most of them if they did not take
the time to read it.

jinstall · **Posted:** Wed Dec 27, 2006 3:09 am

So far so good here. The shifting was harder, but I miss the MB shift quality it used to have. The TC seems to be a little bit smoother and not so agressive when it kicks in. I still have not had a real chance to test it out yet. I have only gotten it to activate in short sperts, to and from work.

kjfishman · **Posted:** Thu Dec 28, 2006 12:10 am

kjfishman wrote:

Startrng a new thread to keep comments about how the recall impacted us in one spot. than be buried in one of the other threads.

First day back and I think mine shifts better, much firmer. I didn't notice a big difference in shift points. It seems to go into OD a bit earlier and I think that is a good thing. The new TC seems to be an improvement. On the negative side the transmission does seem louder now. I haven't taken any kind of road trip or towed the boat yet to comment on eithor the fuel economy or towing power yet.

some additional notes Took a road trip and on when heading back home the next day (after it sat outsdie rather than in the nice warm garage) it wouldn't go into over drive for a good 10 miles then it was ok. Checked the fluid when I got home and it was above add but not full. Went back to the dealer and they checked the level and said they are supposed to add fluid if is above the add line?

CATCRD · **Posted:** Thu Dec 28, 2006 2:39 am

kjfishman wrote:

some additional notes Took a road trip and on when heading back home the next day (after it sat outsdie rather than in the nice warm garage) it wouldn't go into over drive for a good 10 miles then it was ok. Checked the fluid when I got home and it was above add but not full. Went back to the dealer and they checked the level and said they are supposed to add fluid if is above the add line?

That's normal, it won't shift into overdrive until the trans fluid comes above a certain temp.

Ripster · **Posted:** Thu Dec 28, 2006 7:50 am

Get that fluid level after a very long drive to make sure it is at top operating
temperature to the very top hole on full hot.

Fabian · **Posted:** Thu Dec 28, 2006 12:17 pm

First of all, great forum! Lot's of helpful info.

I have put about 200 miles on my Jeep since the recall (21.5K miles total). Previously, I had no reflashes of the computers and I had no trans problems that I knew of. With the exception of having the EGR valve replaced twice (8K miles and 19K miles), the Jeep ran great.

After the recall the trans definitely shifts smoother and seems to shift less frequently. The shift points seem higher (in terms of rpms) now. The shift point into OD is right at 60 mph, which is definitely higher than it used to be.

The loss of power is noticable. Before the recall, it would really take off from a stand still and pull hard. I used to describe the Jeep as feeling like a very fast tractor (which I loved). Now it has lost some grunt. I haven't calculated my fuel mileage yet, but given that the engine revs higher, I can't imagine the mileage will improve.

With this recall, DC has defrauded me. I paid a premium price for a vehicle with premium performance (295 lb-ft of torque and good fuel economy), and DC just took some of that performance away without compensating me. I have already begun consulting my attorney and would be interested in being notified of any class action suits in the works.

BTW, my CRD is my 5th Jeep (a Wrangler, 2 Cherokees, and a Grand Wagoneer). Until this recall, I was a diehard Jeep fan.

alljeep · **Posted:** Thu Dec 28, 2006 12:52 pm

Fabian wrote:

After the recall the trans definitely shifts smoother and seems to shift less frequently. The shift points seem higher (in terms of rpms) now. The shift point into OD is right at 60 mph, which is definitely higher than it used to be.

The loss of power is noticable. Before the recall, it would really take off from a stand still and pull hard.

Excellent description and the same results I've had. What's missing here is the "holeshot" we used to have from a stand still. I used to really accelerate hard starting around 1500 rpm - now it takes 2500-3000rpm before the TQ lets the power flow.

I do believe we still have our full towing capability once at speed as I can cruise down the freeway between 1600-1800rpm all day - just like before. But the acceleration from a stand still is certaintly anemic now compared to the "good old days" of 2005.

donlvnv · **Posted:** Sat Dec 30, 2006 1:07 am

I got my Jeep back today, appears to shift ok. Didn't get to drive it much but will after NYE & day.
The part replaced were:
1. CECAF370 CONVERTER 21046004
2. 4275086-AB LABEL GEN 14086100
3. 56044737-AJ MODULE TR 8035028

gsbrockman · **Posted:** Fri Jan 05, 2007 10:17 am

Took mine in December 19th......picked it up the 21st. My wife was driving up a 6% 2.5 mile long grade, and it shook so bad she said it felt as if it was on some interstate rumble strips. Did it a couple more times on less steep grades. Called the ol' dealer back up, dropped it off, and later found out the original F37 convertor was bad....finally got it back the 29th. After convertor #3 (two within less than one week) we figured all would be well. We took the back roads back home from the dealer (most of which can only be safely driven at 45 mph) and it did great...o/d off. A few days later, around 75 mph on I-75, it shuddered and bucked yet again. The wife was also coming back from her Mom's, and it did it around 60 mph or so once again.

My CRD (now at 24k miles) does feel weaker after the F37. Mine seems to hit 5th at 62 mph or so versus 58 mph or so before. Before, a little throttle input around those speeds would speed up the CRD. Now, with the same throttle input, it downshifts too easily and hunts gears more than it ever has. Not happy.

I'm gonna call my dealer and see about getting a DC Rep involved. I've already looked into the KY Lemon Law info in the owner's manual. I only owe around $9,244 on my CRD......pisser is, I traded in a great 2002 Jeep Liberty Sport because I'm a diesel freak (I also own a 2003 Dodge RAM 2500 HPCR CTD) and 270--280 miles per tank outta the 3.7L was about it......occasionally, I could see 300 miles per tank. I owed nothing on the 2002 KJ that was traded in on the CRD. Yep, I got more creature comforts, but I also have acquired more stress & headaches.

All the 2006 owners are at a slight disadvantage due to the 3/36k warranty.......My '05 has 7/70k.

Greg

{copied & pasted from another thread}

DnA Diesel · **Posted:** Sun Jan 07, 2007 12:37 pm

I would love to see an old and new torque convert compared for stall speeds. I first though we'd been upped by a few hundred rpm, maybe 200-300. I actually think it's much more, based on where the shifts are happening, maybe 500-600. This is especially noticeable when you see the converter lock-up, there appears to be a lot more slippage in 5th prior to the lock up, I see a little over 2000-2050 or so drop to 1700 as soon as the converter locks up. This tells me that there is 21% slippage [(2050-1700)/1700 x 100%] at the converter just before lock-up. This seems ridiculous...the extra heat as well as wasted fuel, etc... is surely occuring with this new set-up. This also tells me that this is a crappy, low-quality, "loose" converter, to be having that much slippage.

Now some folks will tell me, the "diesel's torque is doing that." That's BS, torque is torque...a ft-lb is a ft-lb. In contrast, I have a TurboAction 'tight' 10" converter sitting behind a 475hp big-block 440 in my Charger and even though it's design stall speed is 3800 rpm (to get quickly to the torque peak of 520 ft-lbs at 3900rpm[dyno]). It's design and build quality ($500+, furnace brazed, needle-bearing, HV pump) result in an engine speed of 2100 rpm at 60 mph vice theortical (by gearing/tire size) 1975-1980 rpm...that's only 6.3% slippage at 2100 rpm for a converter stall-rated at 3800. When I hit the gas at 60 mph, the engine flashes to 3800-ish and the fun begins, but otherwise, the tight converter wastes very little energy and causes little excess heat to build up through slippage.

That's why I know that the TC behind the CRD is a low quality, 'loose' coverter. I suspect that even with the flash and torque reduction, the manners of the Libby would be much nicer with a high-qulity low-stall converter. Clearly DCX upped the converter stall big time as part of their plan to remedy what they thought was a transmission deficiency. If it was a problem, I'd rather have an A-518 or 48RE tranny, but I suspect a new pump HV pump would have worked well with the original converter in the 545RFE.

I'm beginning to regret having the F37 done, although I am willing to go $500 out of pocket to put something like an APS 1500-rpm converter into the tranny with a high-quality, high-volume pump, if DCX would just say, OK, we'll keep the warranty stuff going since you put out for the components that are really causing the problem.

Just some Sunday morning ramblings...

Cheers,
Duey

F37 before and after comments...

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