I have an older Craftsman tractor 917.25512 14hp 5 speed. When I drive the trator the it goes along OK then it slips and then grabs. This happen most in the 3-5th gears. If I go in 1 or 2nd it does not happen much. I replaced the belt and the idler pulley looks OK. I just had the trans open and all gears have their teeth. It is a Spicer 4150-6. Any suggestion would be appreciated. Thank you - John

I had one of those years ago that would slip sometimes,

Have you tried belt dressing on the belts to give them grip? Just spays on

Or there may be some adjustment along the way that will take up slack in the system.

Roger

If your on a hill it will usually slip and it can also slip if the teeth are dull

Thank you both. The tractor seem to slip on flat ground more than hills.The new belt is made of something other than rubber so I don't know if the belt dressing will work.