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Discussion Starter #1
Hi,
I have a '75 elky with 350 and 4auto, and I'm planning to swap a 4 speed from 80's truck.

My question : how is the drivability with truck gear ? And about the transmission tunnel, does the 67-72 tunnel bolt on the the 4 th gen ? Or is it completely different floor pans?
 

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Deputy Director, Region 3 PA (west)
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My question : how is the drivability with truck gear ? And about the transmission tunnel, does the 67-72 tunnel bolt on the the 4 th gen ? Or is it completely different floor pans?
There were two different manual transmissions offered in the mid 80's to late 90's half ton trucks. One was the "granny low" non-overdrive unit, which is really not suitable for a Camino, unless you're doing some really heavy duty trailering. The other is essentially similar to the old three-speed manual trans, with the addition of an overdrive gear. The gear ratio spreads on that one are kinda strange, with the 1st, 2nd and 3rd rather close, then a big step to the overdrive 4th. i have a 1987 data book at home, so I can give you the ratios if desired.
Can't help you on the tunnel question.

Bill
 

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Discussion Starter #3
Thx bill, yes I'd appreciate the ratios cuz I found multiple 4 speed transmissions for free near by.
 

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Deputy Director, Region 3 PA (west)
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Attached is the GM Data Sheet on the 1987 transmissions. The R/V models are the full size trucks, M models are small vans, G & P models are full-size vans and S/T are the S10/S15 small trucks. You don't want the SM465 transmission. As I stated before, that's the "low-low" first gear with no overdrive. The MM7 trans used in the full-size trucks is decent. The ratio spread between 1st and 2nd gear is large, but the 2-3-4 ratio spreads are quite driveable.

Bill
 

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Discussion Starter #6
Deal alert.

Just found an 85 elky with 5.3 and 6 speed for ~ 10k, runs and drives.

Most likely gonna go with it instead of the fugly 4th gen.
 
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