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420AT (DCT) shifting hard, banging occassionally

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I rode the wife's 420 a bit this weekend.  She rode the (formerly mine, but apparently now hers) Rubicon and decided she likes the Hondamatic better, so guess the 420 will be going away.

 

I've never liked how the DCT shifts in auto mode.  I've ridden them in stock form, and didn't like it.  It feels like the transmission doesn't know which gear it should be in, and it shifts at the absolute worst times.

 

So Saturday, while riding the farm on her 420, I had a couple of times where I was going through muddy ruts, and gave it more gas, and when it tried to shift, I got a banging noise from the transmission, almost like it was stuck between gears.  I let off the gas both times and it went into gear and was fine after that, but obviously of some concern.  To me it sounded as if the transmission started to downshift, then decided to upshift immediately, and things got hung up between gears for a second until I let off the gas and it knew which gear to go into.

 

It shifts perfectly in ESP mode, and shifts fine in auto mode when toodling along, and also shifts fine in auto mode if you hammer it.

 

It isn't stock.  Has SRA secondary from a 420, which is about an 18% gear reduction, and has a speedometer fixer module from Rapid Revolutions.   I'm wondering if that might be causing the computer shift "uncertainty"

 

Anyone have a DCT that has similar "gear hunting" issues when shifting in auto mode?

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going out on a limb here, as i know nothing about auto's other than they are junk !..lol. with the GR, after market mixer part, its giving the cpu false readings to shift the transmission bro.

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Yeah, that's what I'm wondering.  Hasn't done it until recently.

 

Found this on the old crappy board.  Might try changing the oil with some fresh synthetic, see if that does anything.  If it doesn't, will probably pull the GR.

 

Have a buddy who will probably buy it for his kid, so not like I'm "getting rid of it" LOL.  If it breaks, it'll come back to me to fix it!

 

https://www.hondaatvforums.net/threads/at-shifting-problems.47151/page-2

 

https://www.hondaatvforums.net/threads/2016-trx420fa-not-shifting-properly-or-not-at-all.103466/

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Shade might be onto something , I seem to remember reading about having to disconnect something when running gear reduction , cause it throws off the controller with a false reading 

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Yeah, that's what the Rapid Revolutions module is for.

 

The gear reduction changes the speedometer reading, so it doesn't shift at the right points in auto mode.  The module is programmed to the gear reduction, to put the shift points at the right points.

 

I've been nosing around and looks like it's a pretty common problem, even on stock machines with the DCT's.  @Mac102004 mentioned it in a thread on the old board when the early DCT's were being discussed.

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