Trasmission Yoke to transfer case drive shaft

[vanhow10]

I have the original GM automatic trans adapter plate for my 305C. The current tranny is the 3 speed on the column and the transmission yoke on the drive shaft going to the divorced transfer case is a 16 spline. If I move to an automatic such as a 700R4 to get overdrive, how do I know which transmission yoke to get, i.e. Spicer 1310, 1350, 1330 to match to the 700R4 which is will be 27 spline? Or I might need a 32 spline yoke depending on the transmission.

[LEWISMATKIN]

Two questions (1) which adapter do you have? And (2) the u-joint is the spicer# 5-153x. Hope this is of some assistance.

[vanhow10]

Thanks, not sure which adapter I have, I only have limited automotive experience. I will try to check the universal joint park number to verify which one it is.

[LEWISMATKIN]

There are two adapters. The first type will only accept the single range hydramatic. It was in use through 1963. The second type will accept the house shaped pattern of powerglide & turbo 350 for the chevrolet block. These two types of patterns will not interchange.

[vanhow10]

I think I have the second type then, it had a worn out powerglide tranny attached.

[AZKen]

Don't worry about the slip yoke/ujoint for the intermediate shaft.....yet.

First figure out if your adapter will work with a 700r4 and has all the correct parts. Correct flex plate , input shaft and bolt pattern. Then find a 700r4, mount it and arrange a suitable cross member for the transmission. Decide how you are going to shift it and what to do with the clutch pedal and parts. This is not going to be easy even for a person with knowledge. You say you are limited. It's not going to be real cheap either.

The "intermediate" drive shaft and its yokes and ujoints are later, and easy. Don't throw anything away. There are several folks on here who can tell you exactly what to look for in your adapter parts.

It is possible to get all screwed up. Buying a trans, having it built and finding out you need this or that, have the wrong adapter parts and other issues. Yokes, Ujoints and driveshaft mod shops are plentiful. It's the trans fit-up to motor you need to study. 700r4's have 27 (before 1985) AND 30 (after 1984) spline input shafts. Outputs all the same, 27. 1987-1992 are the best years. 1987 got refined and 1993 got computerized. The 700r4 is THE super transmission. Good torque, overdrive and will handle a BBC just fine. There is a "K" case for 4x4. Has a big "K" cast on it. May or may not be necessary. Could be hard to find depending on a persons area.

Consider a Lokar shifter for around $275. Easy to install, looks like a truck 4 speed, built-in neutral safety switch, no linkage to worry about and adjustable.