Hi, just bought an 82' SR5 4by longbed in pretty good shape for $1800. The truck runs great, however the PO said the syncros were bad. The shifting is real sloppy and the tranny grinds when up or downshifting in third. What are syncros? Are they easy to replace? Thanks! -Lance

 

in a transmission, the synchronizer, aka synchro, is meant to speed up or slow down the rotation speed of the shaft and gear so that they are traveling at the same speed. when they are traveling at the same speed, the clutch can be released and the gears can come into contact smoothly. if they were traveling at uneven speeds, there would be a big clash of the gears and it would be very rough and bad on the gear teeth.

i don't know about replacing them

 

Drguitarum is correct with the description. To replace syncros you'd have to take the transmission apart. However, you could also have a dragging clutch, bad pilot bearing, or bad input shaft bearing based on your description. In all cases the tranny would be coming out to remedy the siuation (except maybe the dragging clutch).

I'd suspect you'll find you have more than just a snycro problem when you tear into it. I'm not trying to be negative, but it's just an educated guess based upon years of experience. You may be better off pricing out another transmission, or looking towards a more durable replacement option. Good luck.

 

Thanks for the help guys!