Converting auto to 4 on the floor...

[toddtheodd]

Ok... my 72 c10 is an auto matic with a th350, and I picked up a 4 speed out of a 72 c20... with a bunch of other parts as well. So... where is the best guide for converting from auto to standard? Also, I need like a parts list with pics to see what I'm missing and what I need to replace.

[rsavage]

You will need the following if you are using a stock truck 4 speed ( I'll probably forget something):
Transmission
bell housing with rear mounts, clutch fork, and mount bolts.
4 speed crossmember (mounts towards the front and the rear mounts on the bellhousing mount to it).
Z bar set up with ball for block
Flywheel, clutch, throw out bearing and pilot bushing
High hump for 4 speed, trim ring for boot and boot
dual pedal (brake & clutch) set up with clutch pedal and rod that attaches to z bar.
Linkage rod to z bar.
standard trans inspection cover
three bolt starter that bolts to the bell housing if you have a starter that now bolts to block
Front section of drive shaft will need to be lengthened and a conversion u joint will need to be used (the yoke on the 4 speed has larger cups than the 350 yoke on the drive shaft has).

Since I am currently converting from 4 speed to 200 4R, I would suggest that you take the top ears off the cross member and bolt them back on with 3/8 grade 8 bolts after the bottom of the crossmember is installed. Saves a lot of wrestling, swearing, and possible brake and gas line damage. You will have to remove your auto crossmember and if it is the stock member it will be riveted in. Again, if you can separate the ears that go to the top of the frame from the main piece it will be easier to remove. Angle grinder and air chisel for the rivets.
Good luck.

[toddtheodd]

&*$%!!! I need the high hump floor board?

I thought the 4 speed standard transmission was the same length as the TH350...?

How bout I just post a pic of what I have, and y'all tell me what's missing and what needs replaced.
Hell... tell me what the names of these parts are as well.
And yes, I'm pretty sure I'm going to have to replace that long bar thingy on the right that has the metal thingy hose clamped to it. Don't know what it is, but it looks like a Jimmy Rigged fix for something the PO didn't want to fix right...

[toddtheodd]

Oh... and besides the parts... what is the best guide to use?

[toddtheodd]

There are no guides on this?
Nothing to recommend?
...
I can't believe that at all.......

[rsavage]

Yes, you will need the high hump. That 4 speed is too tall to fit under a low hump. I'm sure that there are useful maunuals, I just don't have any in mind that I could refer you to. Google "installing a 4 speed in a 67-72 chevy truck" and see what you come up with. I would suggest that you seek out a 67-72 that has the 4 speed in it and look it over carefully taking some reference photos. If you could find one in a junkyard, you could get the missing parts off of it. You are missing parts, most significantly the bellhousing, high hump, and crossmember. I would not use that clutch pedal, I would buy a clutch/brake set up used - they are cheap. The "thingy" is the piece of clutch linkage that goes from inside the cab through the firewall to the z bar. It is not a straight piece and should not have anything hose clamped to it. There is probably a threaded hole on the left side of your block where you can thread in a "ball" for the z bar. I wouldn't use the bolt on one in your photo as I do not believe it will work with the correct cast iron truck bell housing. You will flywheel bolts that are longer than the ones holding your flexplate on and you will need the correct shoulder bolts for the clutch. Don't forget to install a pilot bushing in the end of the crank before installing the standard trans.
I don't know what you hope to achieve by the switch to the manual. These truck tranny's are basically 3 speeds as you will rarely ever use first (very low gear). It is a big job that is not for the faint of heart. You will need help with the transmissions and the proper tools. Good luck with your project.

[toddtheodd]

Do the humps just bolt in? Or will I need to learn how to weld?

[harrdawg54]

The high humps bolt in....but you will have to cut out the opening for the hump. I had to do this when I swapped out my cab. It was super easy.

[unclewatts]

I got it! find someone who has a manual truck and wants an automatic and just trade trucks!

[toddtheodd]

Ok...
So the question of the moment then is...
What standard transmission has both of the following:
a) Will fit under the small hump
b) Is the same length or longer than the TH350. I can shorten my drive shaft, but I can't make it any longer. (I have a 1 piece drive shaft in a long bed)

[rsavage]

The truck 4 speed requires the higher hump. It is shorter overall including the bellhousing than your THM 350. A drive shaft shop like Fleet pride can make you a new tube that is longer or you can possibly find a used shaft. If you use your driveshaft 1/2 of the front yoke, you will have to use a conversion ujoint with smaller cups to fit your front driveshaft yoke and larger caps for the transmission yoke that is bolted onto the transmission. Come to think of it, I don't know how you could use a one piece shaft as both the transmission yoke and differential yokes are fixed - you wouldn't have any sliding room to slide the shaft forward to remove it or install it. You probably would have to go to a two piece shaft. Brighter minds than mine are on this site - I'm sure someone could tell you for sure.

[nickp51chevy]

I ran into a guy last week who has a 67 long bed with a 250 (i think) and he told me that he just put a T5 from a Camaro in and it works just fine. So what I would suggest is getting a Camaro T5 and an S10 T5 and swapping the tail shafts on them to get the shifter in a good location. It would be a little work but you would get a 5 speed. The work would involve moving the speedo gear to the new location for the short shaft of the s10. I have seen plenty of write ups about that. There is even one on here I believe. I know there is more info on this but I can't remember it all right now. Search around for T5's on here you should find a bunch of stuff.

Just my .02

[57larry]

in this same vein, I would like to install a muncie 4 speed in my 72, do I need the high hump floor piece?

[rsavage]

I don't think so. I have a muncie 4 speed in my 66 and it is a low hump. The muncie M 20-22's have a slide in yoke so it presents no problem with a one piece drive shaft. The Hurst shifter, supposedly specifically for my truck, still needed the handle revamped (cut and moved/welded forward at the stem) as it would have hit the bench seat in second and fourth. The shifter comes up right where the floor transitions up by the front edge of the seat. My 66 was a stick to begin with (3 on the tree) so it was an easy conversion.

[capev86]

yeah....go the camaro 5spd route if you get the right year trans (supposedly certain years are better i hear). a 6 speed out of a newer camaro, vette, etc would be even nicer. you could have a low rear end and still have like 2 overdrive gears. my 72 burb has the saginaw 3 speed on the tree which gives the convenience of an auto (shifter up out of the way) with the fun of driving a stick. if my truck had been a 4 speed model with the non synchro first gear, i would be swapping it out for something with an overdrive. but i don't want to change the configuration of my truck and the 3OT is fun to drive because where they were once prevalent on many cars, nobody knows what they are now.....LOL

[nickp51chevy]

They went to the electronic sender in '89 I think so you'll need to get a earlier one. Or you could spend $300 on a little piece of plastic that changes the electronic signal to mechanical for the speedo. But the "better" ones are the World Class ones, can't tell you much else about them though.

[toddtheodd]

What about the length of the camaro 5spds?
Since I have a custom 1 piece drive shaft, and since it is the LONGEST they will make them, I really don't want to have to lengthen it or go back to a 2 piece drive shaft.

One of the reasons I picked up this tranny is that it came with so many of the little parts I would need to change over to standard. I guess I will go with LMC to replace what I need, and look in the junkyards for 5spds.

Is there ANYTHING that has to be welded... anywhere... when converting from auto to standard?

[nickp51chevy]

Originally Posted by toddtheodd

What about the length of the camaro 5spds?

I don't know what the lengths are, so I can't tell ya. sorry.