I disconnected my battery for about 10 min yesterday to see if it stops. Could be a learned issue in the software. It is so infrequent it will be awhile before I know if re-booting the tranny makes a difference or not. I do remember it was a good while after I got my truck before I felt the first hard 5th to 4th down shift, I would say at least 1,000 miles. Currently I'm just around 3,000 miles.

I had the same tranny in my 2013 KR Eco and never had this happen. This tranny has been around for awhile and you never hear about any significant issues with it.

If the re-boot does work for say 1,000 miles then they have a software issue which is what I really believe it is.

I would ask/recommend some others with this issue also disconnect your battery for 5 to 10 min and lets see if it helps. Either way report back here your findings



Bob

 

I doubt the adaptive transmission profiles are going to be erased by a battery power cycle but it's worth a shot I guess.

I had hard downshifts since new. I'm almost at 10k miles and I'm still getting them. I come from manual transmission vehicles and this is my first automatic daily driver. For a while, I almost wanted to consider it normal. The hard downshift feels like someone first learning how to drive a manual. It's extremely jolting. For the most part, it's seemless. But every now and then, it ranges from a slight clunk to an extreme jolt that bottoms out the transmission / engine mounts.

 

Well at this point I have nothing to lose so I went out and disconnected the battery. Dealer still never told me what they did the first time, no way it's a tsb that they said originally because nobody else has heard of one to fix this. Between the HEATED cooled seats and the clunking it's kind of taking some of the fun out of a new truck. Love the look and so many other things just hoping they get these two items fixed.

I did notice when I got back the first time my oil life was at 100% - and I didn't have them change the oil. Does this reset on a battery disconnect? When I head back to the truck I'll try it since I disconnected the battery. Just trying to see if that's all they did to my truck.

 

I didn't notice what gear I'm in, but I have noticed what you are talking about. 5.0 4x4, Lariat, 3.73 diff.. Seemed odd. no clunk (metal sound), just a very strange downshift.

 

Ok I know this is nuts,, but ever since that really hard 5th to 4th downshift yesterday my truck has a nicer feel when driving it, more of a lighter feel to it when taking off from a stop. Meaning it's easier to push the petal down and have the truck start moving. Feels a lot more like my old truck when driving it. When letting off on the petal it seems to coast like I want it to where before it felt like to much engine braking when I didn't want it. Even the (normal) down shifts are a lot smoother now. I hope this keeps up!

 

Good point about the oil change life, I will have to look. I don't think so because my radio stations were still loaded. Problem is I recently changed my oil at 1700 miles to dump the break in oil and to change to a synthetic I wanted to use.

Will be interested on you findings!


Bob

 

Did you do the battery disconnect??



Bob

 

No,, at this point I'll wait and see what happens without trying anything.

 

Bob, I can verify that disconnecting the battery has no effect.

Either the tranny has non-volatile memory, or the defect is inherent in the system, meaning that it will hunt for a gear on downshift and then clunk into the one it picks regardless of learned memory.

 

Add mine to the list as well. I am lucky it has only happened a few times in the first 2100 miles. 3.5 Eco, 3.55. Happened from 5th to 4th in normal mode, not experienced it in sport or tow mode.