The 3-point control works much smoother, still jumps say 1" at a time, but, does not bang hard enough to break stuff anymore. The Service Manager had gone for the day so I could not get any tech data on the how or why of this repair.
I ordered an L3400 today and just came across this thread tonight. Does anyone know if this plagues the '06 models? I am guessing not but wanted to make sure in case I need to bring it up with the dealer tomorrow. Either way, I think I will stop by early next week to have them attach the mower I plan on buying and have the setup tested pre-delivery. Also the dealer told me the R4's are on backorder for about 4 weeks, in the mean time they will deliver it with R1's and replace them when the R4's arrive. Seems fair to me..
The proof will be if they put the mower on for you and you lift it and drop it a few times. Make sure the throttle is set at an "operating RPM", over 1500 will do.
I just got a L3400 in June. The 3Pt adjustment is sensitive, but seems nowhere near the problems previously posted.
It takes a bit of practice to move your lift, but it is not a problem.
FWIW-the only trouble I see is that the lift control is not linear. On mine, it seems that the more you pull back on the 3Pt lever, the quicker and more forceful it comes up. I get almost no lift in the first 40% of the lever, and a bunch more after that. I am lifting a 900 lb 84" finish mower.
I found a little practice works well here. Once you are on to it, it is not a real problem.
Again, I don't know if this is the same on earlier models.
my new 3400 was delivered today and in the flurry of it all, i wasn't really able to test it but the delivery guy told me that kubota is fixing the problem with a new valve and are clearly marking crates. not sure exactly how they know but he said that mine had it so no swap was required. he was fully aware of the problem and said the shop did a bunch of warranty work to get everyone back in working order but hadn't seen any issues recently. I will fully test tomorrow and see how it feels.