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jeepwm69

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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So, since the wife has now claimed the 2005 Rubicon, trying to get this DCT 420AT sorted out and sell it.

 

Took the GR back off last week, put everything back stock.  Shifted better, but at wide open throttle it will still bounce off the rev limiter, especially in 4th and 5th gear.  If you ride it easy it shifts through all 5 gears fine.  In ESP it will shift 1-5 seamlessly, even with throttle pushed to the stop. 

 

Wife and I took a ride Saturday, and I took this Rancher.  Did fine in trails, mud, etc.  I did notice that after putting it in 4wd, it wouldn't come out of 4wd without blipping the throttle sometimes.after putting the selector back in 2wd.

 

FSM says if it shifts fine in ESP but not in auto mode it's speed sensor or throttle position switch.

 

The rear speed sensor is new, because I had to trim down the old one to use with the gear reduction.  That led me to look at the front yesterday.  Took the plug off, cleaned it out with contact cleaner and dialectic greased it.  Had a hard time getting the connector to click back in place, but finally got it, and now the problem seems worse, not better, which seems to continue to point at the front speed sensor.  Ordered one from PSN, so hopefully that will get it shifting right in auto mode.  It does fine cruising around, just doesn't want to shift out if you're gassing on it very hard.

 

@Melatv and @toodeep seem to be the best at troubleshooting these DCT Ranchers.  Anything else I should be looking at?

 

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Replaced the front speed sensor yesterday.  No change.  Still rides fine under normal use, but requires blipping the throttle if I'm at WOT as it will bounce of the rev limiter in 3rd and 4th, but will upshift if I let off the throttle for even a second.

 

So since I have two need speed sensors, that leaves the TPS, or the miles or wring and the ECU as being the culprit.

 

I'm debating on selling it as is, or getting my buddy's kid's 420FA and swapping the throttle body and maybe even the ECU to see if it makes a difference.

 

In any circumstances other than a drag race on pavement, there are no issues, but I still want it to be "right" when I sell it.

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Sooo, got this one out again yesterday.  Swapped the ECU and throttle body (for the TPS) onto the machine.

 

Then it sat for a few weeks again.

 

Decided yesterday it was time to ride it and clean it up and list it.

 

Got on, rode it out to the duck hole, but didn't get on it too much.  Shifted fine at low speeds. 

 

Got on it, and when coming to a stop, get this horrible grinding noise, so at this point I'm thinking I'm going to have to get under the front cover again, because the sound seems to be the transmission trying to downshift as I'm braking.

 

On the other hand, as I roar from a dead start to full speed, it now shifts all the way though all 5 gears without any problem so I guess swapping parts around did do something after all.

 

Then I figure out that it's the dang rear brakes making the horrible noise.  If I only use the front brakes, everything works great, no weird noises!

 

No idea what's going on with the rear brake, and I hate that rear disc setup on these and the Rincons, so I think I'm going to list it as is, with the "Honda, rear brake issues and let someone else figure out if they want to fool with it or just use the fronts like I do on all of my machines LOL

 

It really is a sporty fun little bike to ride, but I hate the auto mode shifting, as did the wife.  In ESP it shifts smoothly and has no issues, but I need my left hand to hold a beverage.

 

 

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Oh, and my buddy's bike still ran perfectly after swapping parts, so looks like it's another situation where something wasn't connecting just right, but removing, cleaning, and reinstalling seems to have restored whatever connection was loose.

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2 hours ago, jeepwm69 said:

Then I figure out that it's the dang rear brakes making the horrible noise.  If I only use the front brakes, everything works great, no weird noises!

 

No idea what's going on with the rear brake, and I hate that rear disc setup on these and the Rincons,

 

 

 

 

 

Looks like my rear brake problems are "normal" which is interesting because they didn't always do it, and they don't do it on my buddy's 420FA.

 

But now I'm going to have to mess with it!

 

https://www.rinconriders.com/threads/noise-when-braking-rear.10162/

 

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Interesting find jeep, disk brakes ?? Have you tried riding the back brake a tad just to see if that makes.... Drive line chatter due to slack might be whats going on.....or maybe try this to see if it's slack in the driveline .... When it you brake... Try adding some throttle to it at the same time to keep the driveline slack down little as possible ... If my idea seems kinda off, well ..... I got that -:;())$&@ gut bug going round (wish i knew where i was when i got tagged, cause someone would be getting an ear full, maybe even good couple hard licks with the Missouri white knuckle soup bone) dang thing is making me feel hazy.... Even kinda drunk.......anyways your post on that noise has my attention.... 

Edited by _Wilson_™
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Sold this one yesterday to a local guy.  He is going to use it on his farm, and me being my usual salesman self said "Well you don't want this for farm use, you need a footshift, air cooled model!"

 

But he was dead set on an IRS automatic.  I sold it for $3K.  With the Warn winch, Foreman wheels, Hondaline front bumper, and 500 top end and Weisco programmer he got a deal, but I didn't have to mess with figuring out the rear brake noise (I did realize that I put new OEM brake pads in it and THAT is when the noise started).

 

I took it for a ride with the wife and mini-me Saturday, and it ran and shifted perfectly, so hopefully it will be a good machine for the new owner. 

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2 minutes ago, Fishfiles said:

Looks like he got a deal.  

 

Market up here appears to have softened quite a bit, and people are pretty leery of the DCT's.

 

A year ago I probably could have gotten $4K or more for it.

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