Kubota seat upgrade.

[Slong1958]

I have a 2012 Kubota L4400 and I’m upgrading the factory seat because the original one isn’t very comfortable. My nephew gave me a replacement seat, and mounting it wasn’t too difficult. However, the new seat is noticeably heavier than the factory seat, and now I’m getting excessive side-to-side rocking.

The original seat had a small amount of play, but it was controlled and never felt unstable. With this new seat installed, there’s significant lateral movement in the suspension/base. When driving the tractor, especially over uneven ground, it rocks side to side enough that it feels unstable—almost like it could make you seasick.

I’m assuming the extra weight may be overloading the factory suspension or pivot points. Has anyone run into this when upgrading seats on an L4400?

Any advice or recommendations would be appreciated.

 

[470d]

Did you find the solution? To me it seems installing heavier duty springs below the seat would fix this problem, or doubling up with same type springs

 

[BlueKnife]

How much slop is there in these two pivot points? Those need to be pretty tight.

 

[470d]

View attachment 5059467How much slop is there in these two pivot points? Those need to be pretty tight.

That's a really good valid point! Looseness in those points will introduce crazy wobble

 

[Slong1958]

Did you find the solution? To me it seems installing heavier duty springs below the seat would fix this problem, or doubling up with same type springs

Yes I did, I took everything apart and found there were some of the welds had broken on the suspension part. I beefed a few things up one being the front pivot.
I removed the rubber and made it a solid mount up front plus removed the 2 springs and bolted the back down solid.
What I did made a big difference there’s a little wobble but not much at all.

 

[CalG]

Stuffing the spring centers with "firm" upholstery foam is an easy way to up the spring rate.

heck, I've rolled up suitable strips of inner tube, secured the roll with a zip-tie, to stuff in a spring so as to increase the load capacity.

 

[chim]

The last 3 of my 5 tractors have been Kubotas. Although they have been great pieces of equipment the seats were all uncomfortable before being modified due to the KTC (Kubota Tilt Curse). I've noted before that every Kubota seat of mine made me feel like it wanted me to fall onto the steering wheel.

In addition to that, the B7500 sat too low (OK, my fault for being over 6'). That one was fixed by making steel risers that were higher in the front. The L3200 was high enough and the forward tilt was fixed with longer bolts and stacks of washers. The L4240 has a cloth seat that's high enough and a whole lot nicer to sit on than vinyl, but the tilt was still a factory standard when it was made. Using longer front bolts and double-nutting them (kinda like allthread stilts) did the trick.

 

[tradosaurus]

I guess I'm not in my tractor seat long enough to notice being uncomfortable.