I've got a 2600 which has got me stumped. I recently had the hydrostats on both sides re-sealed and replaced shafts and bearings in both, but it was not a complete rebuild. It fixed the leaks and I thought everything was great, however once it warms up the left side gets weak and eventually quits working all together. Shut it off, let it cool down, everything is great again until it warms up, then left side quits again. Both left and right hydrostsats are connected to the same shaft and everything is spinning, did not have this problem before the work was done. Is there some kind of bypass valve inside that could be sticking? It seems weird the way it works great when cold, and the failure is like clockwork after a few minutes. I plan on tearing it apart soon to see if its anything obvious but wondered if anyone has any ideas.