Speedo Calibration
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by pole-shed
I need a gear for a 355 rear automatic . Do I use the red one?
This is for a 1987 700R 275/40/17.
This is for a 1987 700R 275/40/17.
Purple, 43 tooth driven gear, 25513050.
VSS, 25007339 (good luck!)
RACE ON!!!
Instructor
Joined: Mar 2002
Posts: 109
Likes: 0
From: West Bend WI
Thanks CFI-EFI, This sounds like positive info. The car had a green 42 and a red 17, the red broke and I am taking it apart and want to get the right gears in. The speed sensor is a A C 1547C,These are the only numbers I have on it. Where can I get the Gray 15 ,Purple 43,and 25007339 sensor? (Art Carr Trans) Thanks Jim
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by pole-shed
Thanks CFI-EFI, This sounds like positive info. The car had a green 42 and a red 17, the red broke and I am taking it apart and want to get the right gears in. The speed sensor is a A C 1547C,These are the only numbers I have on it. Where can I get the Gray 15 ,Purple 43,and 25007339 sensor? (Art Carr Trans) Thanks Jim
Those are GM part numbers and are probably cheapest from Superior Chevrolet. There is good news and bad news on the VSS. The bad news is, the 25007339 has been discontinued and is "impossible" to get. That is why I followed it by "(good luck)". The good news is, as long as your driven gear had more than 40 teeth, you already have the 25007337, VSS.
http://www.gmpartsdirect.com/ shows both items to list for $5.95 each. Strange they would both carry the same list price. Unless you prefer to buy a $70.00 black box, or better yet, a $150.00 black box, you get off pretty cheap even WITH my consulting fee.
RACE ON!!!
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by pole-shed
I have a 41 Green ,a 17 Red and a 20 Brown on hand, I don"t suppose and of these combos would work.
RACE ON!!!
Instructor
Joined: Mar 2002
Posts: 109
Likes: 0
From: West Bend WI
You are right the green gear has 42 teeth., and I have a brown gear with 20 teeth. Before I bought the car it must have had a 307 that they changed to a 355 and just stayed with the red and green. I want to put the correct ones in as you suggested ( Gray 15 and Purple 43)and I guess I will stay with the sensor I have. I will order the gears tomorrow. Thanks very much for your help. Jim
Thread Starter
Drifting
Joined: Oct 2004
Posts: 1,477
Likes: 80
From: Hawaii
Originally Posted by CFI-EFI
The 17 tooth drive gear and 45 tooth driven gear is what was spec'd for the 3.31 ratio in the G92, Z51, 1984's. I can't believe it will read very close for the 3.45 gears.
Thanks,
James
Thread Starter
Drifting
Joined: Oct 2004
Posts: 1,477
Likes: 80
From: Hawaii
Originally Posted by pole-shed
Where can I get the Gray 15 ,Purple 43,and 25007339 sensor?
James
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Thread Starter
Drifting
Joined: Oct 2004
Posts: 1,477
Likes: 80
From: Hawaii
Originally Posted by Corvette Kid NC
James, did you sell my old rear end yet? The reason I'm asking is that someone contacted me asking if I still had my 36. I told him it was recently for sale again but I didn't know anything past that. I also mentioned the shipping costs involved to return it to the mainland! 
Don't forget to post new ET results! 
Don't forget to post new ET results! 
Can't wait to try out the 3.45, and my new DRs.
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
In this 2000 tpis catalog I have they show that some applications may use 1045089 in place of 25007339. I have no idea if it would work with your vette or not. Its just a note that they have in the gear selection section. By the way, they do not sell the parts, but just give the nos. for reference to a gm parts place.
Large Impressive Member
Joined: Jul 2003
Posts: 65,811
Likes: 71
From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by James93LT1
Aloha Chris, still have your 36. Someone also contacted me today about it...going to see what we can work out. Got my D44 in, and got a brand new ZF6 coming in soon. I think I should have bought a ZR1 from the begining with all the $$$ I'm spending....but I'd be missing out all this fun Can't wait to try out the 3.45, and my new DRs.
Can't wait to try out the 3.45, and my new DRs.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by James93LT1
CFI EFI, I got the 45T driven gear based on a 26" tire (285/40/17)....did I do my math wrong?
Thanks,
James
Thanks,
James
RACE ON!!!
