Some factory C10 equipment Q's

[Mrturner1]

Hey all I have a 1970 C10 LWB 2wd and the PO did ALOT of changing things around. It currently has a 355/th400 and the rest is stock factory running gear which I'm trying to identify today. There was definitely a manual transmission in the truck at one point, the crossmember for that was cut and you can still see the part bolted to the frame. If it was a manual trans from the factory, wouldn't that garauntee it was also an I6 motor? And if THAT is so, would that garauntee that it's a 3.73 rear?

I was under it yesterday chasing a bolt in exhaust system rattle, and I started wondering about drivelines in these long bed trucks. I've never seen a LWB truck that had a one peice driveline. All the ones I peeked under had those two-peice drivelines that were connected at a round cutout in a crossmember. Are there factory one peice drivelines in 1/2 ton LWB trucks?

[SS Tim]

Time to do some research. If the VIN prefix is CE it was a V8 and CS would have beeen a L6.

The powertrain charts and decoders linked in my signature should be a good start on what was what. Then we can figure out the details. But a manual 3OTT or four speed could have been had behind even a 396 in a 70C10.

[budman k20]

I bought a 72 C10 LWB a few years back, and it also had a single driveshaft in it. The PO put a long tail shaft TH350 in it. I drove it home 1100 miles with no drive train problems and didn't vibrate up to 90mph anyway.

[Mrturner1]

I've been trying to get the paint off the SPID, only thing I see are these. Sorry for the black paint in the pic, PO obviously didn't give a darn about this truck, kinda ticks me off somebody would do that.

B85 body side moulding BX2 B side moulding-WIDE lwr
622 gold vinyl trim. 534 white and medium olive

[Mrturner1]

The vin is definetly a CE. Pretty cool that the warranty and Owner Protection Plan made it 44 years under the seat pretty much hidden until I found the truck.

[SS Tim]

Factory 307/3OTT truck. There shouldn't be any engine emblems on the fenders. Colors were nice, Medium Olive and White in a conventional two-tone (white roof and door window frames). The gold trim was actually an ivory color and one year only. It isn't reproduction gold or parchment as a FYI.

[Mrturner1]

According to the VIN and Model decoders I got that it was a V8, long bed fleet, 1/2 ton, from Atlanta, 2wd.

The weird thing is that it has a manual trans crossmember that's been cut out, and it has a column shift

[Mrturner1]

Originally Posted by SS Tim

Factory 307/3OTT truck. There shouldn't be any engine emblems on the fenders. Colors were nice, Medium Olive and White in a conventional two-tone (white roof and door window frames). The gold trim was actually an ivory color and one year only. It isn't reproduction gold or parchment as a FYI.

I think that's an awesome color combo. I was looking at another members white and medium olive but his was the two tone that has an olive stripe down the side and two parts white.

What's the side mounding? It's primered grey but I can see down the side where there must have been rivets to hold trim on. Would it have been the 3-4" wide nice trim?

It could've been any V8 then? And 3.07 rear with no posi I'm guessing, and a 10 bolt?

Did they come with a one peice drive shaft?

[Keith Seymore]

Originally Posted by Mrturner1

Did they come with a one peice drive shaft?

One piece vs two piece is determined by the shaft critical speed.

Inputs to critical speed calculations include: wheelbase, shaft overall length, shaft material, tube diameter and wall thickness, rear axle ratio, tire diameter and anticipated vehicle top speed, as well as any unforeseen system resonances discovered during physical testing.

Changing any of those can make the difference between a particular model getting a one piece or a two piece shaft.

I could envision a small displacement 2wd lwb truck getting a once piece shaft, especially with a lower numerical rear axle ratio, due to a potentially lower top speed and the slower shaft rpm due to the axle ratio.

K

[SS Tim]

Originally Posted by Mrturner1

According to the VIN and Model decoders I got that it was a V8, long bed fleet, 1/2 ton, from Atlanta, 2wd.
The weird thing is that it has a manual trans crossmember that's been cut out, and it has a column shift

Correct it is a 1970 C/10 (1/2 ton) LWB Fleetside pickup built in Atlanta.

Not sure why it is weird. I've seen all sorts of butchery under the pretense of improvement. The fact is the truck was built with a three-speed column shift manual transmission.

Originally Posted by Mrturner1

I think that's an awesome color combo. I was looking at another members white and medium olive but his was the two tone that has an olive stripe down the side and two parts white.

The trucks with the White roof and rockers are called Special Two-Tone that was an option available on your truck but not chosen. It originally only had the White roof as defined by the paint code.

Originally Posted by Mrturner1

What's the side mounding? It's primered grey but I can see down the side where there must have been rivets to hold trim on. Would it have been the 3-4" wide nice trim?

Your truck was optioned with both the upper and lower bodyside moldings which included the tailgate and tail lamp moldings as well. However beeing a base trim truck it did not have the windshield or rear window opening chrome nor the chromed ventilators. The front (only) bumper was painted white.

Originally Posted by Mrturner1

It could've been any V8 then? And 3.07 rear with no posi I'm guessing, and a 10 bolt?

Did they come with a one peice drive shaft?

Again clearly it was built with a 307 2bbl V8 and a three-speed transmission. Per the published powertrain charts it would have been built with an H035(12 bolt) open (non-posi) 3.73:1 rear end on coil springs. There were a number of driveshaft combinations both single and multiple section. Without research I cannot tell you exactly what it had.

[special-K]

The manual transmission came with any engine offers...as standard equipment. Automatic was an option straight across the board. The driveshaft could be custom since the truck has been altered. To tell of a 6 to 8 swap look at the motor mount towers where they bolt to the frame (2 bolts each side), is there another hole ahead or behind? Many who swap an 8 from a 6 don't move those, so that can be a tell tale. The 6 cyls only had a fan protector and the 8 cyls had a shroud. The top radiator clamps is where the shroud attaches and 6cyls wouldn't have clip nuts. A manual to auto telltale is often seeing if there there is a clutch linkage block-off. Columns can be swapped. In fact, a total drivetrain swap can be done to look factory. Everything is interchangeable. Many would cut that manual crossmember when going to automatic when it could be removed with a little more work. The manual bellhousing would have bosses to mount to that crossmember where automatics span to the tailshaft housing where it mounts to that crossmember.

[Keith Seymore]

Originally Posted by SS Tim

There were a number of driveshaft combinations both single and multiple section. Without research I cannot tell you exactly what it had.

I asked the current propshaft design/release engineer for the vintage charts but they didn't lend themselves well to reproduction and publishing here (too many, and not in a very good format for historical reference - very fragmented by model).

These examples do give an idea of the amount of detail that goes into defining the driveshaft system.

K

[Mrturner1]

Originally Posted by SS Tim

Again clearly it was built with a 307 2bbl V8 and a three-speed transmission. Per the published powertrain charts it would have been built with an H035(12 bolt) open (non-posi) 3.73:1 rear end on coil springs. There were a number of driveshaft combinations both single and multiple section. Without research I cannot tell you exactly what it had.

I thought you meant 307 was the rear gear ratio, my mistake.

Well the good news is it's already got a 3.73 rear. It's got to much body work (dimples and dings) for me to want to restore it so I recently rebuilt the 355cid that's in it. Did some decent heads and a big ole rumpity 280H cam, RPM manifold and 650avs carb. It has a th400 in it and my next project was to put a big stall converter in it and build the rear end with 3.73's and a tru trac posi. The rear end cost just got cut in half with this peice of news just have to get the posi now.

[special-K]

In the 67-72 GM Truck world 307 = engine and 3.08 = gears. No 3.07 gears in trucks

[mike16]

if it helps at all.....my 72 c10 307 3 spd on the column. has the two piece drive shaft I dont think it was that unusual back then. might be kinda rare now.

[Mrturner1]

How can you guys tell it's a 307cid truck with a 3.73 rear though? I looked at the decoder and the charts but I don't understand how you guys are getting that information

[SS Tim]

Originally Posted by Mrturner1

How can you guys tell it's a 307cid truck with a 3.73 rear though? I looked at the decoder and the charts but I don't understand how you guys are getting that information

OK, lets make this easy.

You stated the VIN prefixes CE, that tells us its a Cheverolet conventional with a V8 engine. This is shown in the VIN decoders linked and thousands of other places.

You provided a SPID that does not indicate an engine or transmission option.

As such the truck was built in a base or default configuration.

For a 70 C/10, 1/2 ton truck the base V8 was a 307 2bbl engine. The base transmission was a column shift manual three speed.

If you were to look at the powertrain charts linked ( http://67-72chevytrucks.com/vboard/s...7&postcount=10 ), you will see that a 70 C/10 with a 307 and a three speed manual transmission was assembled with a 3.73:1 rear end ratio.

3.07 and 4.11 as well as positraction were all optional. However your SPID again does not indicate that any of these powertrain options were selected.

Now the important thing to remember here is this is how the truck was built in 1969/70. What you have now is up to you to determine.

[special-K]

It's real simple. 3spd was standard and 3.73 ratio was standard with 3spd. Optional transmissions and ratios will be listed as options.

[Mrturner1]

Originally Posted by SS Tim

OK, lets make this easy.

You stated the VIN prefixes CE, that tells us its a Cheverolet conventional with a V8 engine. This is shown in the VIN decoders linked and thousands of other places.

You provided a SPID that does not indicate an engine or transmission option.

As such the truck was built in a base or default configuration.

For a 70 C/10, 1/2 ton truck the base V8 was a 307 2bbl engine. The base transmission was a column shift manual three speed.

If you were to look at the powertrain charts linked ( http://67-72chevytrucks.com/vboard/s...7&postcount=10 ), you will see that a 70 C/10 with a 307 and a three speed manual transmission was assembled with a 3.73:1 rear end ratio.

3.07 and 4.11 as well as positraction were all optional. However your SPID again does not indicate that any of these powertrain options were selected.

Now the important thing to remember here is this is how the truck was built in 1969/70. What you have now is up to you to determine.

Ok that makes sense. Thanks for makin that easy