Learn run for 47RE

[Steve M]

I can't take credit for the idea as someone else posted how to do it awhile back. Then my local dealer's service writer told me the same thing when I stopped in for a re-flash. He said do this and then decide if I wanted the re-flash as it's not reversible.

I'd been having an intermittant shift problem with my 47RE. It would shift to second and third all at once giving the sensation that it was slipping and jerking. It would only do it if I let off the throttle alittle after a launch just as it was ready to shift to second. That and it would shift to O/D and lock up the T/C while I was moderately pouring on the coal instead of holding the gears longer like it should.

What I did was disconnect the batteries for a couple of minutes, then reconnect them. Turn the key to run but don't start the truck. Slowly push the accelerator to the floor and back to idle. Turn the key off. This apperently teaches the PCM the voltage ramp from idle to WOT.

When I closed it up and drove off, I couldn't believe how much better the shifts were and how the transmission responded to the throttle. I'd been missing my '01's 47RE because of the way it shifted not knowing this one just needed a "learn run".

Very good info and thanks to whoever it was who posted it!

 

[djbobo]

Ok I'll do it just for fun.



I had the re-flash done some time ago, however.



dj

 

[ttreibel]

I wish they had a reset button for all the computers in our cars and trucks..... and when will they start emailing us with there wants.

 

[Tony T.]

Steve: Just wanted to check back after a few days from seeing your post. Is your 47RE still shifting ok ( the way you wanted it to) and have you noticed any difference in mileage since you done the learn run thing. Also did you disconnect both negative and positive or just the positive cable.

 

[Steve M]

Still happy with the shifts! No difference in mileage but I've kinda let that go and have been enjoying the power. I disconnected both negative terminals.

 

[Tony T.]

10-4Oo.

 

[dieselpilot1969]

so how does it go exactly, do you disco the positive terminals or the negatives or both and for how long?

 

[fishjack1]

Anyone else tried this? Does it really make a difference?

Just curious

 

[Steve M]

I don't think it really matters whether you disconnect the negatives or positives or all four as long as you remove the 12vlt potential. Leave them off for a couple of minutes to allow the memory in the PCM to dissipate.

It made a big difference in mine because mine was apparently fowled up enough to cause erratic shifts. If yours isn't having trouble it probably won't make any difference but it certainly can't hurt. If mine ever starts giving trouble again in the same way, I know what I'm going to try first!

 

[RATTLINRAM]

About a year ago, my truck started unlocking the TC in OD for just a moment while running 65 mph. This seemed to happen at any given time, but after about a dozen times during a month long period, I did the APPS reset procedure and the truck has never done it again. SEE HERE

 

[fishjack1]

I guess this procedure only works on newer (24v) trucks and does not apply to my '96?

 

[ray1933]

It Works

Till I started reading this thread I was going to take mine to the dealer and have them explain how and why mine shifted the way it did.



Did the learning thing yesterday and man what a difference in the shifting.