I found out the hard way that if you think that the pick in the shuttle shift maybe plugged just back flushing the system is not enough it may get your machine to work again for a short time but as I found out that if you do not brake the machine down and clean that pick screen properly you will end up like I did having to replace $2000.00 in parts. When I got mine apart and found that pick up located behind the valve body of the shuttle shift. Was just not plugged but the inside was full of junk that had been back flushed into it and then possibly recycled back thru the system plugging it more. So if you believe that that pickup is what is causing you machine to move sluggishly you better clean it or you will burn up all the parts in the shuttle shift.