[Z06] Smooth shifting
Thread Starter
Le Mans Master
Joined: May 2005
Posts: 6,366
Likes: 249
From: Fort Lauderdale, Florida
Smooth shifting
I just replaced my Mobil 1 trans fluid with the new Dexron VI and did the Anti-venom shifting mod. The difference in shifting smoothness is remarkable. I also have tried Red-Line ATF and after 34,000 miles the trans has never shifted this smooth, it's like a different car. The difference was noticeable immediately.
Dogface
Joined: Jul 2004
Posts: 25,974
Likes: 120
From: At the Beach, FL
St. Jude Donor '15, '17
Originally Posted by chiefDave
Same here 
I went with RP Syncro Mesh and loved it. TTT
Dave
I went with RP Syncro Mesh and loved it. TTTDave
It is a new bolt to replace the original one that has a spring and ball type plug that is at the top of the tranny. This is the part that makes the notchy feeling in the trans. I bought one but have not installed as yet. There are those that have also tried to shim out the original bolt as well with copper washers. There is a thread on this on the other forum if you do a search on Antivenom shift mod it should get you in the right place. PM me if you want more info. Take care, Don
Race Director
Joined: Sep 2005
Posts: 11,060
Likes: 291
From: Pasco WA
FWIW, the antivenom plug made no difference in my '02 Z. Save your money. Changing the fluid will be my next attempt. Just missed a 3-4 shift the other day, when I really could have used it, if you know what I mean...
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Melting Slicks
Joined: Jul 2004
Posts: 2,846
Likes: 5
From: Sandy Ego CA
I didn't do the bolt thing, I went to the local auto parts and got a copper oil drain plug washer that was used as a shim behind the tran indent bolt, if I remember it was close to 0.072 thick and cost whopping$3.00 bucks for two washers. This is by far the best mod I have done for shifting. I have a Hurst and you can bang gears like no tomorrow and I have never missed a shift, It act's as though the Hurst has a mind of it's own and using Ranger's suggested shifting method this set up is Golden. I highly recommend it.
If you go back 4 or 5 months and look through the CF archives there are plenty of details with pic's regarding this mod. Look for the Antivenom mod, there is more than one post
If you go back 4 or 5 months and look through the CF archives there are plenty of details with pic's regarding this mod. Look for the Antivenom mod, there is more than one post
Burning Brakes
Joined: Sep 2002
Posts: 924
Likes: 0
From: Dothan AL
I have a Hurst Shifter in my 03 Z. Went to Autozone and picked up a two pack of the 13/16th copper drain plug washers for $1.88.
Took longer to jack car up and put jack stands under it then to remove detent bolt and install washers.
Changed fluid to the Royal Purple Syncromesh and what a difference !!
Smooth shifts and little effort needed, still have positve feel for each gear because of the Hurst, downshifts are effortless.
26,000 miles on original trans fluid and it was ugly to say the least.
I would recommend changing your fluid at 15,000 miles on first change.
Took longer to jack car up and put jack stands under it then to remove detent bolt and install washers.
Changed fluid to the Royal Purple Syncromesh and what a difference !!
Smooth shifts and little effort needed, still have positve feel for each gear because of the Hurst, downshifts are effortless.
26,000 miles on original trans fluid and it was ugly to say the least.
I would recommend changing your fluid at 15,000 miles on first change.
Thread Starter
Le Mans Master
Joined: May 2005
Posts: 6,366
Likes: 249
From: Fort Lauderdale, Florida
First item-Dexron VI is the newest version just barely on the market yet, but all the new 6-spd auto trans are coming with it and GM will be phasing it into all other transmissions effective now. You can buy it at dealers now by the quart. Only a few bucks a quart. More slippery with greater shear strength.
Second-I didn't buy the Anti-venom part. I also got a big copper washer for 70 cents and made my own. The Anti-venom part is $60 and eliminates the spring loaded ball.
Third-Anyone who is still having shift problems after these fixes, probably still has the stocker shifter, not the most precise shifter I've ever driven. Any brand will be much better. I have a Hurst with a beautiful Vetteessentials two-tone shift boot.
Second-I didn't buy the Anti-venom part. I also got a big copper washer for 70 cents and made my own. The Anti-venom part is $60 and eliminates the spring loaded ball.
Third-Anyone who is still having shift problems after these fixes, probably still has the stocker shifter, not the most precise shifter I've ever driven. Any brand will be much better. I have a Hurst with a beautiful Vetteessentials two-tone shift boot.
Burning Brakes
Joined: Sep 2002
Posts: 924
Likes: 0
From: Dothan AL
Where it is
The bolt is on the passenger side of transmission. You cannot see it but if you reach up toward top of trans on passenger side about mid ways of transmission you will feel a bolt going in side of trans. It is a 15/16 or 24mm, either size works, bolt and you just take it out. No fluid will come out and no spring to fly around either.
I used two of the 13/16th copper drain plug washers on mine. About 1/16th total thickness with both washers. Just place them on bolt and tighten bolt back up again.
Here is a picture of where the bolt is from where someone wasseeling a bolt for $60.00 that did not have the detent ball in it at all.
I used two of the 13/16th copper drain plug washers on mine. About 1/16th total thickness with both washers. Just place them on bolt and tighten bolt back up again.
Here is a picture of where the bolt is from where someone wasseeling a bolt for $60.00 that did not have the detent ball in it at all.
Advanced
Joined: Feb 2005
Posts: 61
Likes: 0
From: Clearwater Florida
My2Dogs, Good job, Thank You! Took me a lot longer to find and buy the 15/16 socket, and the 1/8 washer than the 10 min under the car. Next will be Mobil 1 change to make it even better, thanks for the info!
Safety Car
Joined: Sep 2000
Posts: 3,604
Likes: 396
From: Austin, TX
Spent this morning playing around with the antivenom shift mod (washer method). I realize everyone is different (and I respect that), but these changes made my 2000 FRC feel like my old 65 Beetle.....
For what its worth, Redline D4ATF seems to work better for me (to reduce notchy shifting) than the Mobil-1 or Amsoil options. That being said, like with many mods, there is not really a good way to perform a valid comparison/experiment.
For what its worth, Redline D4ATF seems to work better for me (to reduce notchy shifting) than the Mobil-1 or Amsoil options. That being said, like with many mods, there is not really a good way to perform a valid comparison/experiment.
Advanced
Joined: May 2005
Posts: 90
Likes: 0
From: Gainesville Ga.
While we are on this subject of "anti-venom" mods let me ask--- I went under the car 03 Z and located the tranny drain (on bottom) and fill plug (on drivers side) the fill plug had wires on it which could detach easily. OK I did the drain and fill with RP syncromax THEN I went to do the washer deal on the detent bolt (passenger side) but could not because it had wire on it too that I couldn't get off so I couldn't back the bolt off. What is up with that?? Is my car "different"?? Thanks for any help you can offer. 
Racer
Joined: Jul 2004
Posts: 327
Likes: 0
From: McKinney Tx
Originally Posted by jwenger
While we are on this subject of "anti-venom" mods let me ask--- I went under the car 03 Z and located the tranny drain (on bottom) and fill plug (on drivers side) the fill plug had wires on it which could detach easily. OK I did the drain and fill with RP syncromax THEN I went to do the washer deal on the detent bolt (passenger side) but could not because it had wire on it too that I couldn't get off so I couldn't back the bolt off. What is up with that?? Is my car "different"?? Thanks for any help you can offer.
