cor66vette

There is similar thread going but I didn't want to hi-jack it with my question.

I am experiencing this whether the car is cold or completely warmed. I can't shift smoothly into 2nd from 1st: only FROM 1st- neutral to 2nd or downshifting is effortless. I experimented with different speeds and RPMs and it doesn't make a difference. It's to the point where I'm thinking about bringing it to a dealer. Shifting is getting less fun.

Does this sound familiar to anyone? Thank you

ersatz928

I have the same issue...sometimes a little grind (more like one "click" of syncro interference) from 1 to 2.....cold or hot...250 miles on my GS....I am not too happy with this but will probably live with it, rather than have the dealership mechanics drop the rear subframe to replace the transmission. This seems to be a hit-or-miss issue with these Tremecs......probably due to unit-to-unit variability of mechanical tolerances of the syncros. And yes....I am pushing the clutch fully to the floor....and yes I know how to drive manual trans cars......
What are the last 5 digits of your VIN? (trying to see if there is a production date trend).

l2vette

Try draining and refilling your tranny with new GM recommended fluid. I had the same problem and the new fluid made a huge difference.

SCorvette08

are we assuming a M7 if so it gets better but there is some adjustment that the dealer can due or a MGW shifter which i did

cor66vette

^ ^ ^ Thanks for that, ersatz928. I agree with living with it, and I will also, particularly if it means the tranny has to get pulled, or if any invasive fix is needed. But I may want to find out.

ersatz928

It has "new GM fluid" : the car has 250 miles on it.....!!

ersatz928

This is an internal syncro problem...nothing to do with the shifter linkage and/or adjustment of it....

cor66vette

Thanks, guys. If it's fluid, or an adjustment, I'll see about the dealer doing that. I don't want go the MGW route- at least not at this point. It's an M7, yes.

cor66vette

Ouch!

SCorvette08

i did the same i used Mobile 1 atf better especially in cold
it was rated better than redline ,RP most of all of them

yeller z06

My car does the same thing, kind of stiff to shift into second especially when cold. But I seem to recall similar behavior in my C6 and many many cars these days have a beefed-up 2nd gear synchro because that's where most of us (Americans) are going for the big speed, fast shifts, and just JAM IT IN when shifting. So to avoid warranty repairs, they've made the synchronizers bigger and more robust, which means that they are a bit more difficult to use, especially when cold.

Shoot, go drive a manual transmission Ferrari. It's worse than a truck. You'll appreciate the Corvette a lot more, trust me.

JC 2004

Take a look at this...

JC 2004

FYI. This is just a portion of the complete instructions. You can google and see the whole solution.

ersatz928

I am not talking about "higher shift effort when cold"..I agree that that is normal for many manual gearboxes, and different lube can help that.

My issue (and I think the OP cor66vette) is poor 2nd-gear-synchro performance....which causes a brief grind or click due to gear clash as you pull the lever into 2nd.

snork

wasn't the M7 designed to go from 1st to 4th unless you were at a rpm greater than 3500?

cor66vette

@ JC 2004 -Possibly an adjustment may help my problem?

A little while ago I called a tech I trust at a dealer and discussed my shift situation. I'll be swinging by sometime next week for him to test drive and determine a course of action. I'll post the results.

cor66vette

Yes, same here.

ersatz928

The CAGs was designed to "game" the EPA fuel economy test...a properly designed and manufactured manual gearbox should have properly working synchros throughout the normal engine RPM range....from idle to redline.

JC 2004

Your original post mentioned not being able to make a smooth shift, which made me think of the old alignment issue tsb. If your getting a grind it could certainly be a synchro issue as well. I'm sure the dealer will get it sorted out for you.

I had a 4th gear synchro go on a Viper I had in 1999 and they replaced the trans and never had another issue.

Larry/car

I went from a 2014 manual to a 2017 manual. My 2014 shifted smoothly once broke in. The 2017 at only 250 miles is stiff, I expect it to smooth out in the future. Both cars are base Stingrays without MRC.