ttr 4400 HST - moves great to backward but moves weak to forward ? some problem here

Spanner · Sep 11, 2017

Yes, it can.
"Speed Fix" is a type of Cruise Control. It is electric operation via dashboard button and internal components. You may need dealer support for this issue.

These are versatile machines and the swiveling seat concept is very interesting.

When you tried in Reverse-Mode, did the problem reverse?

oldnslo · Sep 11, 2017

Since this has the swivel seat and controls it could be electro-proportional controls on the HST. If this is not getting the correct signal it could make the HST weak in one direction and operate fine in the other direction.

Like Spanner asks did this problem follow the reverse mode of operation?

joaorodrigues88 · Sep 12, 2017

today I test in the reverse mode, and no changes... the problem is the same. The only difference in the mechanics, it's a reversible valve for the direction.
I looked under the tractor to check the linkage, and the only thing I can see it's 2 pistons that are individual pressed by the movement of the pedal, I think it's hydro valves.
I think I need to call to the local service..

oldnslo · Sep 12, 2017

joaorodrigues88 said:
today I test in the reverse mode, and no changes... the problem is the same. The only difference in the mechanics, it's a reversible valve for the direction.
I looked under the tractor to check the linkage, and the only thing I can see it's 2 pistons that are individual pressed by the movement of the pedal, I think it's hydro valves.
I think I need to call to the local service..

Are you saying there are two different valves the foot pedal operates? I.e. one on each side..

If yes then this sounds like the pump is hydraulic pilot operated and yes you will probably have to contact the local service company. I believe you stated all the fluids & filters were change Who changed all the fluids and filters?