Rough 2-3 Shift

jeepdan · **Posted:** Wed Oct 12, 2011 6:43 pm

Has anyone figured out what causes the rough 2-3 shift at 35mph during very light throttle? I have learned to avoid it most of the time by maintaining some acceleration which produces a nice smooth shift. Both of my CRDs do it and they have probably done it since new.

dieseldoesit · **Posted:** Thu Oct 13, 2011 10:20 am

I think mine does it as well.. though I have the GDE trans tune..

warp2diesel · **Posted:** Thu Oct 13, 2011 2:36 pm

Drive a few miles and with out shutting off the engine, open the hood and check your fluid level. If you are lucky, you will add some ATF+4 and get on with life. When I installed my Suncoast/Transgo I had the problem until I topped off the ATF+4 by checking it after driving a few miles. Going around the block did not do it for me.
The next cheapest thing to fix is change out your trans filters just in case you have a problem like a split filter. If you catch the split filter that draws the fluid out of the pan that is sucking air in time, you will be lucky. Foamy ATF+4 on the stick may indicate a split filter.
If your luck is bad, you will be doing some more involved repairs.

jeepdan · **Posted:** Thu Oct 13, 2011 5:24 pm

Thanks for the replys, My CRD has done it ever since I bought it four years, 75,000 miles ago. It now has 106,600 miles on it. I serviced the transmission with Valvelene ATF-4 and Mopar filters at 78,000 miles. The hot fluid level is correct. The rough shift has not gotten worse and I have never have had any other different shifting problems. If it was a TCM learning issue, you would also think it would get it right after 75,000 miles of driving.
My other recently purchased CRD does the exact same thing, records show that it had the f-37 trans recall done in 2009, so I'm pretty sure that it's fluid and filters are fairly new. I have learned to avoid very light throttle 2-3 shifts at 35mph, but every once in a while I will forget and it will bring me out of a day dream. :shock:

CATCRD · **Posted:** Thu Oct 13, 2011 6:45 pm

Both of mine have done it, ever since new. No fluid or filter change ever helped. One CRD even has the transgo shift kit and still does it. I just keep some light throttle there to avoid it.

Oh, and it's actually the 3-4 shift at 34mph.

jeepdan · **Posted:** Thu Oct 13, 2011 6:55 pm

CATCRD wrote:

Both of mine have done it, ever since new. No fluid or filter change ever helped. One CRD even has the transgo shift kit and still does it. I just keep some light throttle there to avoid it.

Oh, and it's actually the 3-4 shift at 34mph.

Thanks, that's assuring, and thank you for correcting me. :oops:

grywlfbg · **Posted:** Thu Oct 13, 2011 6:57 pm

Timely thread. My wife has recently started complaining about this. We have an '05 w/ ~93,000 on it. It's had the original filter recall, F37, and Euro TC and pump done over the course of its life. I also added a deeper pan for more fluid.

Initially I thought it might be motor mounts or u-joints but I drove it the other night and realized it was only that one shift that was bad. If it was motor mounts or u-joints I would assume other shifts would feel weird too. I don't hear anything - just feels like a really slow shift. I check the fluid level regularly and it's been fine but I'll check it again. I guess I could order another set of filters and swap them and the fluid. At least the new pan has a drain plug :BANANA:

So GDE TCM doesn't help? :cry:

CATCRD · **Posted:** Thu Oct 13, 2011 7:17 pm

Wait, you're right, the GDE TCM tune eliminates it because it locks the TC in 3rd gear and then shifts lock to lock after that.
In the other jeep, the worst is when you're coasting down a slight grade while picking up speed. When you hit 34mph - CLUNK!.

grywlfbg · **Posted:** Fri Oct 14, 2011 4:52 pm

GDE TCM tune on the way. I'll update the thread with results.

dieseldoesit · **Posted:** Fri Oct 14, 2011 4:57 pm

CATCRD wrote:

Wait, you're right, the GDE TCM tune eliminates it because it locks the TC in 3rd gear and then shifts lock to lock after that.
In the other jeep, the worst is when you're coasting down a slight grade while picking up speed. When you hit 34mph - CLUNK!.

I have the TCM tune.. doesn't solve the problem..

grywlfbg · **Posted:** Mon Oct 17, 2011 7:54 pm

I had a chance to drive the CRD some more this wkend. My hard shift is at 20mph so that would be 2-3. It'll give you whiplash it's so bad. Fluid is full. Is this tranny done for? I'm still planning to drop in the GDE TCM and swap fluid and filters. Wonder if I should add some Dr. Tranny to it as well? If it's just one shift that's bad can it be repaired or should I plan to buy a new transmission? Dealer or competent mechanic?

grywlfbg · **Posted:** Tue Nov 15, 2011 7:03 pm

So an update here...

I installed the GDE TCM and the problem went COMPLETELY away. All gears shifted like butter. My wife was ecstatic.

However, after about a week the hard 2-3 shift has returned w/ a vengeance. I'm guessing it was during some kind of learning mode that the shifting was smooth and now something's changed and it's forgotten? Can I just permanently put it into learning mode?

grywlfbg · **Posted:** Thu Jan 19, 2012 4:34 pm

Another update. Had the dealer do the fluid and filter change as I was busy and I also wanted them to take a look at a coolant leak (another thread). They did the change and did a "quick learn" and the Jeep is shifting perfectly. It's been fine for 1.5 weeks so we'll see. Worried it'll do the same thing it did when I installed the GDE TCM - worked fine for awhile and then the hard shift came back.

Rough 2-3 Shift

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