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Discussion Starter · #1 ·
Guys as you might have gathered from my previous post I am in
the middle of a tear down and re-build of a Borg warner T5 from my
1984 camaro.

Now to my question. Do any of you know how the fifth gear ratios are
calculated. In my case I have 2 gears which make up the fifth gear which
I believe is .72 final ratio.

The larger helical gear has 55 teeth and the smaller one has 31.

So what I am trying to figure out is how the final ratio is calculated.

I believe for that year transmission I may be able to select different
ratios for the fifth gear set , so any info you got would be most
appreciated..

Thanks... X711.
 

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Discussion Starter · #2 ·
Yep I did a google search too, found more for mustangs than GM.

I was trying to figure out if I could use a.63 or 68 ratio instead of a .72
ratio for the overdrive gear set. Since they come as a pair.. it might work.

I will call around tomorrow..

x711
 

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x711 said:
Yep I did a google search too, found more for mustangs than GM.

I was trying to figure out if I could use a.63 or 68 ratio instead of a .72
ratio for the overdrive gear set. Since they come as a pair.. it might work.

I will call around tomorrow..

x711

Why? There is almost no rpm difference.
 

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Discussion Starter · #4 ·
Well going to a .68 from a .72 would drop the revs slightly but as you indicated not really enough to make a huge difference.

Anyway I called about 10 places today looking for these gears and finally found one company that had them in stock. The gears I went with are made by TTC automotive and are new !

So a rebuild project is waiting for over the holidays. lol.

Its funny really, I started out just wanting to replace the clutch, but curiosity got the better of me so I looked in the transmission as my speedo was not working, I figured the gears might have been striped. After cracking the T5 open, there they were bigger than life both fifth gears with missing teeth, eh "Not good"

The plastic speedo gear that was on the output shaft was at the end of the output shaft just floating. Its usually kept in place with a ball bearing and spring. It was not even making contact with the speedo drive gear.

I also noticed that there was less than a quart of oil in the T5, so all in all
I might have just got to it in time .. I also got a master rebuild kit for it so I should be good to go.

Thanks... X711
 
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