Torque converters, trannys, and F37....OH MY!

chadhargis · **Posted:** Wed Nov 28, 2007 2:58 pm

I have had a shudder at around 50mph in 4th gear and around 62 in 5th gear under moderate throttle or load when the transmission doesn't downshift. If it downshifts, all is well, but if it remains in the higher gear, it feels like the little Jeep is having convulsions.

I finally took it to the shop, and they re-did the F37 and installed a new torque converter. Low and behold, I still have the same problem. I gave the mechanic a ride, and showed him what it's doing. He told me that he'd see if he could figure out what the problem is.

Is sure feels to me like a clutch slipping, but what the hell do I know? It's something in the transmission for sure, since it doesn't do that all the time, only in 4th and 5th gear immediately after shifting to those gears. Lock out overdrive, or punch the throttle to the floor and there is no shudder.

I'll let you guys know what they find out. Also, I have noticed a little weeping around the fuel heater connection hose. I forgot to mention that to them this morning, but so far I'm not sucking in much air. I bleed the system maybe once a month and get a little bubble out of it, but nothing much. I'm holding out that a recall is put out for that part.

gmctd · **Posted:** Wed Nov 28, 2007 3:19 pm

I'd say it's the Inmotion tune on the standard torque convertor - I s'pect the only cure will be the SUNCOAST SOLUTION

You can prove that by popping a stock oem-tune ECM under the hood..................

uncaged · **Posted:** Wed Nov 28, 2007 4:59 pm

Tranny line pressure too low to hold the lock-up clutch in the TC while the torque of the diesel is overcoming its CoF?

gmctd · **Posted:** Wed Nov 28, 2007 5:06 pm

Yes, and TCC too weak to hold Diesel torque - normally, TCM sends ECM a Torque Modification Request in times of peril - 'ease off, yer killin' me' - the oem T\C was insufficient to contain the oem tune - how much moreso when power curves have been enhanced, as with the Euro tune in the Inmotion reflash - they've admitted nothing can be done with the basic TCM tune, so only option is to upgrade the hardware

scrambledKJ · **Posted:** Wed Nov 28, 2007 5:06 pm

It's not the inmotion tune. My crd has 13k miles and is doing the same thing. I figured the converter was locking and unlocking and having a siezure. I had he f37 and new TC before 6500 miles. I'm gonna drop it with the dealer next week and see what they say. I figure I might try to get a new TC and see if they will allow me to pay the difference between theirs and a suncoast. Might have the lawyer wife write them a love note. Cannot decide which atlanta area dealer to take it to. Anyone near ATL with experience?

Travis

chadhargis · **Posted:** Wed Nov 28, 2007 6:10 pm

It's not the inmotion tune. I had the same issue before the tune too, just finally decided that the random downshifting and shudder was bugging me too much so I took it in. I wanted to wait till closer to the end of the warranty period so I won't end up having the same thing happen shortly after the warranty runs out.

The dealer, Hansen Jeep, in Nashville has been really great. I dropped the Jeep off on Monday and they overnighted the TC in and had me ready to go Tuesday. Of course, that didn't fix it, and I dropped it back off today. The service writer called me just a bit ago and said they spoke with "engineering" (presumably Chrysler) and said they have been authorized to replace the pump, clutches, and that it's possible they put the incorrect torque converter in the first go round. He said that they would have it until Friday. Friday?? I'm amazed! I figured it would take them a week or two to get it fixed with all the parts that have to be shipped in. But Friday...wow! That's fast.

The pump makes a LOT of sense. I told the tech that it felt to me like clutch slippage. He agreed, and if the pump is not supplying enough pressure, then that makes perfect sense as to why it would slip.

I'll post up another update when I hear more.

Oh...another example of how good the dealer is...I've bought a fuel filter from them twice, and they had it in stock both times! Cool!

Pablo · **Joined:** Thu Feb 02, 2006 10:06 pm **Posts:** 1201

You may also want to do the trango at the same time. I wish I did it as I have the suncoast and it has not totally cleared it up. Also, if the line pressure is too low to hold it, it it is either a design flaw (which the transgo should fix) or a ripped seal in the tranny. A tech on the other site said just about everyone with the 545RFE that has had issues is because of a ripped seal or the cheap torque converter.

I will get a tranny shop to go through this thing eventually and make sure it is right.

gmctd · **Posted:** Wed Nov 28, 2007 6:58 pm

See if they'll install the clutch pack from Suncoast, with you picking up the tab for the clutches - see if they'll do the same with the Suncoast TCC

chadhargis · **Posted:** Wed Nov 28, 2007 9:25 pm

I asked about the Suncoast TC, but was told that they can only install OEM parts.

gmctd · **Posted:** Wed Nov 28, 2007 10:30 pm

Too bad - those clutches were developed for the Hemi trucks for drag racing - work just fine for hd street service: towing, ORM, SEGR, Inmotion, Edge, etc.........as does the T\C - same deal, billet housing, the hd TCC clutch, aluminum stator, brazed fins, Timken bearings, but with the stall speed way lowered for Diesel service

No shame on them - they're bound by the constraints of DCX warranty policy, where it's 'my way or hit the hiway"

danoid · **Posted:** Thu Nov 29, 2007 9:57 am

I've had similar issues, also 45 mph in 3rd gear, light load. Seems to be worse after a heavy acceleration. I think it's engine software.

Why would the transmission care what happened 3 seconds ago? It only transmits torque. If I can turn on / off the phenomonon by my rate of acceleration up to that speed, it points to software.

The real kicker for me was when I got the shudder at 20 mph in second gear. The torque converter is unlocked at that speed. It seems unlikely that the converter clutch was causing anything.

The fact that the Inmotion tune does it also just (to me) means that it's not a fueling calibration value, rather an air flow control problem. I doubt Inmotion rewrote all of the engine software.

As an investigate, does ORM / not ORM have any affect on the shudder in your CRD?

gmctd · **Posted:** Thu Nov 29, 2007 10:56 am

Could also be TCM software - if you could easily duplicate the tremors at will, it would be interesting to install a toggle switch in the TCC apply line, where you would instigate the event several times in a row, open the switch and try for another incident, see if it's the emcc illogic.

I'm just not in ours enuff to in-depth report, but it's never occured when I have been in it, B4 or after Suncoast - the Edge module was installed when we got it in Sept, and F37 had been recently done in Mar07.

Once, after Suncoast, when rolling up to a Stop sign, it acted like it was hanging in two ranges, or the TCC was locking\unlocking rapidly - cleared up and nothing since.

I did spend two glorious hours and 140mi in it Thanksgiving after doing ORM, where I was able to get rail pressures, fuel rates, and other DCX enhanced data, but no shudder

chadhargis · **Posted:** Thu Nov 29, 2007 11:14 am

I'm wondering if the F37 is flashed to the TCM or the ECU? I have the Inmotion tune, and I'm wondering if I need to send it back for programming now that they redid the F37.

gmctd · **Posted:** Thu Nov 29, 2007 11:21 am

It's flashed to the ECM, and Inmotion will reflash it for free if DCX messes it over - does your invoice say you got the reflash, or just the trans rework?

CATCRD · **Posted:** Thu Nov 29, 2007 12:57 pm

chadhargis wrote:

I'm wondering if the F37 is flashed to the TCM or the ECU? I have the Inmotion tune, and I'm wondering if I need to send it back for programming now that they redid the F37.

I believe it's flashed into both. The one in the TCM is not reversible.

chadhargis · **Posted:** Thu Nov 29, 2007 8:27 pm

Yes, the sheet the dealer gave me said, "Redo Recall F37".

When I get my CRD back, I'll send the ECU off again.

gmctd · **Posted:** Thu Nov 29, 2007 9:40 pm

I'd suggest giving it a week or two on the DCX reflash for comparison - maybe a month - or until you've verified that it is or is not healed, or at least much better

chadhargis · **Posted:** Thu Nov 29, 2007 10:21 pm

Yeah...that was my plan. No reason to have it re-flashed if I have to take it back to the shop again. Sending the ECU off for a re-flash means I'm down for 2 days at least.

Goglio704 · **Posted:** Thu Nov 29, 2007 10:26 pm

I doubt they redid the flashes. There is no point to it, and they run the risk of botching the flash and having to replace the module. I'm not even sure their equipment will let them overwrite a flash unless it is for a newer version.

chadhargis · **Posted:** Fri Nov 30, 2007 11:30 am

Humm...that's interesting.

I even spoke to the tech directly when I was giving him a ride along and he said he "re-programmed the computer" and would try it again.

Torque converters, trannys, and F37....OH MY!

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