S-10 Forum banner
1 - 7 of 7 Posts

·
Sonoma
Joined
·
19 Posts
Discussion Starter · #1 ·
I am having problems with grinding when I upshift. If I do not wait a second to let the rpm's drop before I shift, this is when it grinds. When I drive like an old man, there is no grinding.

My local mechanic thinks it is probably the synchronizers, and I am going to have it checked out at a tranny shop later today. A couple members of this forum also thought that it was the synch's in my earlier post.

I want to understand how the synch's work, what they do, ect. Can anyone explain them to me? Also, what would cause them to go bad?

I will have to have a transmission shop do the fix since I can't do it on my own (sure wish I owned a lift...;) ) so what can I expect this to cost? Is this a common thing on trucks with 120,000 miles?

Thanks
 

·
Big Engine, Little Truck
Joined
·
639 Posts
In the most simplest of terms, the syncros allow you to shift into gears without having to double-clutch. That is; you do not have to clutch, pull out of gear, clutch again, change gears. Think of a semi tractor/trailer. They do not have syncronized transmissions and must, therefore, double-clutch every gear change.

They wear out for several reasons: over-time, just like anything else mechanical, due to abuse, just like anything else mechaical or due to lack of lubrication, just anything else mechanical that moves.

If your syncros are gone, a full rebuild of the transmission would be in order. Anytime gears get worn, they create little tiny pieces of metal floating around. Not good for the longevity of other moving parts in the transmission. Hope that helped.
 

·
Sonoma
Joined
·
19 Posts
Discussion Starter · #3 ·
thanks for the explanation superunknownmoto.

Will double clutching lessen the wear on the synchronizers?
 

·
Work In lack of Progress
Joined
·
113 Posts
yes, your synchronizers allow the gears to reach the same speed before they engage thats what double clutching does, but you are gonna grind a lot trying to double clutch it all the time and most likely mess the tranny up more, my synchs are starting to go out as well. 236,760 miles lol
 

·
Oasis Customs
Joined
·
6,851 Posts
when your clutch is engaged your gears on the first shaft arnt moving (or are bearly moving) if you have it out of gear and the syncros are there to make those gears match the speed of the gears on the 2nd shaft conected to the drive shaft, and making it easier and faster to get in gear.
 

·
matt
Joined
·
26 Posts
my truck started to do that, it wasn't an audible grind but i could feel it in the shifter. i changed my trans oil and it felt like a brand new trans, smoothed right out
 

·
I Dropped it like its hot
Joined
·
150 Posts
I can shift in everything except 1st and reverse without the clutch (300 000 kms) is that bad?
 
1 - 7 of 7 Posts
Top