NX55 HST Jerky Transmission at Low Speed

[CloverKnollFarms]

Did this MANDATORY service bulletin fix the surging HST issue. Im looking at an NX4510 now, and I need to know if I should avoid this model.

 

[TN8Man]

Did this MANDATORY service bulletin fix the surging HST issue. Im looking at an NX4510 now, and I need to know if I should avoid this model.

I'm waiting until after the new year to get my NX in the shop.

 

[CloverKnollFarms]

I'm waiting until after the new year to get my NX in the shop.

Has the issue been bad?

 

[TN8Man]

Has the issue been bad?

I only experienced surging (at low speed or creeping) when using the PTO stump grinder or after a long hot day of mowing on hillsides.

 

[Eat Your Veggies]

Did this MANDATORY service bulletin fix the surging HST issue. Im looking at an NX4510 now, and I need to know if I should avoid this model.

My NX has been flawless. Apparently, even before the update, only a few machines had the issue. So there’s no way to know if mine would have been affected had the ‘fix’ not been implemented. I’d be more worried about a recent used unit that hadn’t been updated. I’m impressed with the tractor and how responsive my dealer is. Enough so, that I recently bought new pallet forks the kioti grapple from them.

 

[MinnesotaEric]

My 2014 tractor has it bad. And yes, I would avoid this model.

 

[CloverKnollFarms]

My 2014 tractor has it bad. And yes, I would avoid this model.

So the mandatory update did not resolve it?! I’m looking at a 2018 and 2019

 

[MinnesotaEric]

So the mandatory update did not resolve it?!

What mandatory update? The one for 2019 and newer machines? My machine is a 2014 with 800 hours and is out of warranty, and I have no dealer.

 

[CloverKnollFarms]

What mandatory update? The one for 2019 and newer machines? My machine is a 2014 with 800 hours and is out of warranty, and I have no dealer.

It was a recall. Not warranty issue

 

[MinnesotaEric]

It was a recall. Not warranty issue

I never received a recall notice. Insofar as I know, the heresy is that the issue is an electronic control valve that changes the direction of travel which can only be fixed by splitting the tractor in half to access it and replace it.

Kioti NX transmission issues

www.tractorforum.com

 

[TN8Man]

For my situation it was the solenoid(s) that control the valves in the HST and the issue was known but not to me when I bought the tractor nor when I first started requesting warranty repair. The fix was to replace the HST with one that had known good parts. The symptoms (failure modes) I experienced were severe and those particular symptoms have not returned. I don't necessarily attribute my current issue as described in this thread to my original problems and fix. I don't have enough data yet. It could be related or it could be related to the mentioned software fix or something else. The good news is I'm still under Kioti's 6 year warranty.

As far as "Would I by another NX knowing what I know now?"
That answer is yes because other than the issues I have experienced the NX is a great tractor for me at a great price. The original more severe problem was fixed and I think the current issue (much less severe) will be fixed. I'm sure many tractors from different manufactures experience problems and the manufacture/dealer may or may not be totally upfront on what they know for different reasons. The 6 year warranty is a key factor on why I bought Kioti and my thinking was that most defects if any would surface within that 6 year period and so far that has worked out.

 

[CloverKnollFarms]

I never received a recall notice. Insofar as I know, the heresy is that the issue is an electronic control valve that changes the direction of travel which can only be fixed by splitting the tractor in half to access it and replace it.

Kioti NX transmission issues

www.tractorforum.com

The actual recall notice was a simple addition of bonding straps and a new HST program that could be done on the owners property. No dealer visit required. It was issued in 2021.

 

[CloverKnollFarms]

For my situation it was the solenoid(s) that control the valves in the HST and the issue was known but not to me when I bought the tractor nor when I first started requesting warranty repair. The fix was to replace the HST with one that had known good parts. The symptoms (failure modes) I experienced were severe and those particular symptoms have not returned. I don't necessarily attribute my current issue as described in this thread to my original problems and fix. I don't have enough data yet. It could be related or it could be related to the mentioned software fix or something else. The good news is I'm still under Kioti's 6 year warranty.

As far as "Would I by another NX knowing what I know now?"
That answer is yes because other than the issues I have experienced the NX is a great tractor for me at a great price. The original more severe problem was fixed and I think the current issue (much less severe) will be fixed. I'm sure many tractors from different manufactures experience problems and the manufacture/dealer may or may not be totally upfront on what they know for different reasons. The 6 year warranty is a key factor on why I bought Kioti and my thinking was that most defects if any would surface within that 6 year period and so far that has worked out.

So they did split the tractor to replace HST parts?

 

[TN8Man]

So they did split the tractor to replace HST parts?

No, they removed and replaced the HST unit.

 

[CloverKnollFarms]

Well, if I can pick up this 2018 4510 with 200hrs for about $20k… I’m in. The dealer said it’s never had a warranty claim, and they sold the unit new, guy traded in.

 

[MinnesotaEric]

So my 2014 tractor is not covered by this recall thingy. My new dealer hasn't seen any NX series with as many hours (800 now that compared to some of you, is nothing, but they are Minnesota hours), and I shared how the problem has always been there, but now is much, much worse it got this at the end of this summer and that my experience is that the HST seems like it wants a slightly lighter 20D spec hydro-trans oil, but every dealer is using 20C spec oil, and so am I because 20D is hard to get and is 3-4x expensive and not available anywhere locally.

We also discussed clean filters and whatnot, and I shared that my 800-hour service will happen this spring. Without any diagnostic tools, I'm thinking the issue is my solenoid, but the diesel tech I was speaking with shared in the service notes available that it can also be plate tolerances. I guess I'll find out if the complete trans/hydro oil swap and new filters will do anything as I first talked about with this problem come spring when it is warm enough to service my tractor (I work outside).

 

[MinnesotaEric]

For my situation it was the solenoid(s) that control the valves in the HST and the issue was known but not to me when I bought the tractor nor when I first started requesting warranty repair. The fix was to replace the HST with one that had known good parts. The symptoms (failure modes) I experienced were severe and those particular symptoms have not returned. I don't necessarily attribute my current issue as described in this thread to my original problems and fix. I don't have enough data yet. It could be related or it could be related to the mentioned software fix or something else. The good news is I'm still under Kioti's 6 year warranty.

As far as "Would I by another NX knowing what I know now?"
That answer is yes because other than the issues I have experienced the NX is a great tractor for me at a great price. The original more severe problem was fixed and I think the current issue (much less severe) will be fixed. I'm sure many tractors from different manufactures experience problems and the manufacture/dealer may or may not be totally upfront on what they know for different reasons. The 6 year warranty is a key factor on why I bought Kioti and my thinking was that most defects if any would surface within that 6 year period and so far that has worked out.

For my reference, do you happen to have any of those part numbers from your service invoice? I'd like to look it up and see what is involved to swap out.

Thanks!

 

[TN8Man]

For my reference, do you happen to have any of those part numbers from your service invoice? I'd like to look it up and see what is involved to swap out.

Thanks!

Unfortunately I can't find a invoice. This warranty work was done a year ago now and I'm wondering if they even gave me a invoice because I was not charged for any work. I do need the receipt for my records though and I plan on taking the tractor back in for the creeping/recall issue so I will request a copy of the HST R&R at the same time. Once I get the receipt I'll see if it has the info you seek. The shop manager did tell me the solenoid(s) in the HST was the issue and Kioti switched to another vendor/manufacture for the solenoid.

When I got the tractor back it was fixed from the original problems where I would lose reverse travel and major jerky forward travel after a long hot day mowing on hillsides. Once the tractor cooled down it usually worked fine but one time the reverse didn't come back and the shop had to come pick it up and fix it. I still think excessive hydraulic system heat is a factor.

Recall Letter

 

[MinnesotaEric]

Unfortunately I can't find a invoice. This warranty work was done a year ago now and I'm wondering if they even gave me a invoice because I was not charged for any work. I do need the receipt for my records though and I plan on taking the tractor back in for the creeping/recall issue so I will request a copy of the HST R&R at the same time. Once I get the receipt I'll see if it has the info you seek. The shop manager did tell me the solenoid(s) in the HST was the issue and Kioti switched to another vendor/manufacture for the solenoid.

When I got the tractor back it was fixed from the original problems where I would lose reverse travel and major jerky forward travel after a long hot day mowing on hillsides. Once the tractor cooled down it usually worked fine but one time the reverse didn't come back and the shop had to come pick it up and fix it. I still think excessive hydraulic system heat is a factor.

Recall Letter

To be sure, what year is your tractor because the recall has nothing to do with my serial number break?

 

[TN8Man]

I bought the tractor new in May 2019 and the s/n is VW7xxxxxx.