SX3100 coming out of 4 WD on its own

[gaheadrick]

Has anyone else experienced problems with their 4WD selector coming out of 4WD unexpectedly their Cub Cadet Yanmar SX3100 tractor? I have approximately 90 hours on mine and have found it to be a great machine overall. I have a very steep asphalt driveway averaging approximately 24 degrees in slope. When I travel down the driveway with or without a load, even at several different RPMs, it just slips out of 4WD on its own. I have to place my foot on the lever to keep it from coming out of 4WD gear. The dealer discussed the issue with Cub Cadet Yanmar reps and they indicated they have never heard of this problem before. In the interest of safety they split the tractor and could not find anything wrong or out of specification so they replaced all the components of the 4WD. All replacement parts appeared exactly the same spec and tolerance; no apparent difference. The dealer spent time testing the tractor on his sloped driveway without issue and declared the problem resolved. I have the tractor back and find that the problem is actually worse than before, likely coming out of 4WD gear 4 of 5 trips down the drive. More so while idling down at slow speed. No issues going up the drive under load or not. The issue is experienced only going down whether forward or backing down. A contractor working on my site unexpectedly used my tractor while I was away for several minutes to move a load of gravel. It came out of 4WD gear on him too and he hit the brake which allowed a heavy set of semi controlled skid marks all the way down the driveway; something I've experienced too. Fortunately, he was not injured but could have been. This is an extreme safety issue for me. I'm looking for any information anyone may have information, knowledge or experience which might help us resolve the problem. The dealer has been great to work with on this and is coming back out to my site next week to witness this issue so that they can communicate again with Yanmar based on direct experience of the issue. If this issue can be solved this machine would 100% perfect. Any help will be very much appreciated.

 

[dslanec]

I have 55 hours on my sx 3100 and have had zero problems. It is at the dealer now getting its first service done. I have done a lot of loader work with it and had to travel up and down two hilly driveways while doing it and never had this happen. I was always in 4wd as well. Good luck and please report back with any updates.

 

[BuilderML]

I don't know if it would matter but are you in high or low range? Most work should be done in low range to my understanding. If you are in high range have you tried low range to see if you have the same problem? I now have 46 hours on my sx3100 with no issues. I mow a hill side at about a 25* slope in 4wd in low range with no issues. I also do it in forward and reverse without issue. I do not have the loader on while mowing. Hope that yanmar gets it figured out for you. Please post back with your findings. Do you have any ballast in the rear while doing your loader work? If not i would add some as you are putting alot of pressure on your front end.

 

[Gods Country]

I'm thinking it's something simple like the linkage. If placing your foot on the 4wd lever is enough to keep the 4wd engaged I don't believe it's a real serious issue. Good luck with it.

 

[gaheadrick]

Appreciate your reply and questions. I use the low range when doing any loader, blower work and always when ascending or descending my steep driveway. 4WD is very useful going down hill because the resistance in gearing acts for breaking as the rear wheels have the only actual brakes; non in the front wheels. I have ballast in the rear tires and also a 3 point rear plow. The problem occurs under load or without a load. When the tractor was in the shop we examined the linkage assembly, splines, spring, ball bearings etc. The dealer first thought that the tolerances were a little more than he would expect. The decision to replace this whole assembly seemed to be the best potential solution, so that was done. When the new parts were received and inspected all tolerances appeared the same and all the new parts were installed. The dealer took the tractor home to trial it extensively on his steep gravel drive and had no issues, so he thought the problem had been solved. It obviously has not, and he will come out and observe the issue first hand this week. Once he has first hand knowledge of this problem occurring he will contact Yanmar once again to attempt to find the solution. I'm thinking that there may be an issue with the housing or casing tolerances since replacing the internal linkage parts did not solve it. My dealer thinks they may need to replace the tractor if we cannot find a solution.

 

[diesel466]

I have heard of several john deere 2520 and 2720 tractors having this problem. As Your tractor share the same drivetrain, Maybe do a search and see what the fix was. Good luck

 

[gaheadrick]

Excellent reply; many thanks. The research so far indicates that these machines have in fact had several incidences reported of the very same issue. One response was identical to mine regarding the issue and the need to keep a foot on the lever or pin the lever so it cannot kick out of 4WD. One solution response indicated that they replaced the spring between the two ball bearings in this mechanisms with a stiffer spring. Makes sense to me. I will research some more and share this with the dealer and Yanmar. Given that this issue occurs with this drive train with some consistency the response by Yanmar that they "have never heard of this problem before" holds no credibility.

 

[scoutcub]

Out of curiousity, any progress with the issue and/or Yanmar?

 

[gaheadrick]

Yes, the dealer came out to the sight to review the performance issue first hand. They were able to experience the tractor coming out of 4WD on its own every single time they went down the driveway, just as I experience. They brought a new Yanmar SX3100 with them so we could test it on the same slope to determine if it had the same issue. It did not have any problems so we know that it is my machine and its parts that have the problem. The dealer is currently working with Cub Cadet and Yanmar to resolve the issue and I am awaiting their response. It could be that they will replace the spring mechanism in the 4WD mechanism or something else or replace the machine. We'll see. Meanwhile, it is still a real safety issue with a FEL loaded and I just have to keep my foot on the control lever to prevent it from coming out of 4WD.

 

[scoutcub]

I thought you were going to say they left the new SX3100!!! Hopefully they'll fix it or replace it. At least they're responding in a positive fashion!