CRD -5th shift point - effect of F37 recall? ?

impulse · **Posted:** Sun Dec 10, 2006 1:16 pm

There seems to be mixed reviews on the shift point ( to 5th lockup) and what effect the F37 has on it

The poll relates to the last shift going into 5th.

The TC locks up in 4th. Note that RPM doesn't fluctuate ~500 rpm with changes in gas pedal position as it does in 3rd.

Cowcatcher · **Posted:** Sun Dec 10, 2006 1:25 pm

I haven't had the F37 done but I will hold off on the poll as there is no choice for me. Mine has always shifted at about 64 MPH and it seems that until recent post here others had the same experience.

spoonplugger1 · **Posted:** Sun Dec 10, 2006 1:42 pm

As with a digital systems your controls read absolute values, if you don't want a control system to bounce back and forth you have to increase the allowed spread between control accuations. My rig has never had a shudder that I've considered a problem, never more and what you'd feel going over an expansion joint or something in the road. I have nothing at all if I just drive thru the shift change to say 64 mph before I set back to 60. At 56-58 mph it than smoothly shifts back one gear to 4th.

DarbyWalters · **Posted:** Sun Dec 10, 2006 1:56 pm

No shudder...shifts in at about 64mph...first vote...no F37

retmil46 · **Posted:** Sun Dec 10, 2006 3:01 pm

15K miles, had filter TSB done at 7K on my own dime, been reflashed at least twice (no F31 or F37), has always went into 4th at 50 and 5th at 58, drops back into 4th below 55. Only had shudder a few times, no occurrence since correcting fluid level (2 quarts low from factory, corrected at first service), filter replacement, and eliminating air leaks in fuel system.

Ripster · **Posted:** Sun Dec 10, 2006 3:28 pm

From day one final shift 62-64 downshift at 57-58 when slowing down. No change after the TQ and Pump
replacement, they are calling Monday reference F-37 flash will not take in mine, one controller says its an 05
the other says its an 06, so I expect a new ECM by this Friday and then I will vote and comment on the shift points.
No issues at all with the new TQ and pump. Smooth and no shudder, but then I also have the TransGo. So I have
introduced other variables.

Ranger1 · **Joined:** Mon Oct 17, 2005 7:40 pm **Posts:** 1137

Ripster wrote:

From day one final shift 62-64 downshift at 57-58 when slowing down. No change after the TQ and Pump
replacement, they are calling Monday reference F-37 flash will not take in mine, one controller says its an 05
the other says its an 06, so I expect a new ECM by this Friday and then I will vote and comment on the shift points.
No issues at all with the new TQ and pump. Smooth and no shudder, but then I also have the TransGo. So I have
introduced other variables.

If you have the pre F31 flash, and everything works, run away as fast as you can! But if you do go back, let us know what happens to the power levels.

Ripster · **Posted:** Sun Dec 10, 2006 4:06 pm

The problem is if I run, then if it takes a hike, it is my fault for not getting BOTH parts of the F-37 recall. I am tempted, but
then I own the transmission and any problems from here on out.

farout · **Joined:** Sun Dec 10, 2006 4:17 pm **Posts:** 1

had F37 done 12/06/06. No noticeable change in shift points or torque or Hp. Shifts are more solid rather than real smooth. I just want to see if MPG stays the same or goes down.

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

I had the F37 done. You poll is a bit confusing. It shifts @ 50mph and then again at 61mph. I didnt vote because you dont have an option that fits the actual condition of the recall.

CATCRD · **Posted:** Sun Dec 10, 2006 11:42 pm

2005, No F37 or flashes whatsoever, last shift/lockup whatever at 58mph

Got Diesel · **Joined:** Thu Oct 19, 2006 8:13 am **Posts:** 108

I say this has fixed all of my issuse and and I am looking for an aftermarket TQ and will do a chip tune here very soon.

richardkf · **Joined:** Wed Jun 14, 2006 4:15 pm **Posts:** 167

I shift into 5th right about 52 mph and the torque converter engages about 58 mph and there is a bit of drivetrane lag if i am going uphill in 5th until 65 mph. I had all transmission flashes and filter TSB's done. And last week I had the F37 completed. Before the F37, I was going into 5th around 55 - 60 mph and the torque converter engaged around 62 mph. There was an occasional, minor, negligable shudder before the F37. Now there the lag replaced the shudder.

However, since F37, one week into it, there are no "clunks" at all when shifting from park to drive/reverse or reverse to drive and vice versa. Before F37, it sounded like a bunch of bolts were rolling around and jolted the CRD like it was an 18 wheeler. Now it's all very smooth when shifting from gear to gear.

Also when driving, the low gear shift points (1st, 2nd and 3rd) are a lot smoother and less awkward than before. The low gear shift points seem to be the same as they were before The 4th and 5th gear shift points seen they changed to about 3 - 5 mph sooner than before and are also much smoother. It has made the engine feel smoother under light or hard acceleration to me. And no black clouds when accelerating hard (so far).

If the engine was de-tuned (HP and Torque) through the BCM or TCM flashes, it is not noticable. You notice the shift points are different, but you dont feel any power loss from pre to post-flash. If anything, the whole setup feels like all the components were made for each other (engine, transmission, and Liberty). Before the flash, the engine and transmission seemed like they were a bit in conflict with each other with varying levels of smoothness for shifts and the harsh noises that came from shifts from and to park, reverse, drive, etc ...

If you're CRD is on the recall, go and do it now while the parts are still around. The difference is for the better.

Got Diesel · **Joined:** Thu Oct 19, 2006 8:13 am **Posts:** 108

richardkf,I had the same problem like what you were having,and yes I have had the same out come,no more CLUNK CLANK..and like it was goit to fall apart when you take it from park,drive ect.but yes I is night and day diffent and the power in my book is back...I say from a Tech stand point,find a Stealership that has a level 4+++ Diesel tech and get this done..
Manny

no-blue-screen · **Posted:** Mon Dec 11, 2006 11:53 am

Mine does that clunk, but no F37 shows up on the jeep site for my CRD.

impulse · **Posted:** Tue Dec 12, 2006 7:52 am

Please join poll Only 5 have had F37 done? Does it mean that the F37 recall allows for under 1500RPM at 50 mph....

impulse · **Posted:** Tue Dec 12, 2006 6:41 pm

Does the F37 change the last shift to approx 50mph?

litton · **Posted:** Tue Dec 12, 2006 7:25 pm

I think it's the TC lockup that occurs at the higher speed not the 4th to 5th shift point. It's possible that point gets confused sometimes.

BioJeep · **Posted:** Tue Dec 12, 2006 9:41 pm

Quote:

I think it's the TC lockup that occurs at the higher speed not the 4th to 5th shift point. It's possible that point gets confused sometimes.

I'm pretty sure it is the 4th to 5th gear shift that occurs at 64, not TC lock-up.

richardkf · **Joined:** Wed Jun 14, 2006 4:15 pm **Posts:** 167

Torque Converters only lock up in the highest gear.

CRD -5th shift point - effect of F37 recall? ?

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