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I have a 52 body on a 79 short wheel base frame, dropped in a 350 motor with an automatic 400 tranny out of a Nova. It measures out about 58" from center of cup to center of cup. My question is Is there a driveline in the junkyard that will measure 58". I thought maybe a driveline off of a short wheel base truck might work>

Did you use the '79 original motor/tranny mounts? If so, try to find a 'shaft from a short wheelbase halfton with the TH400 tranny.

Or, you could just take your trusty tapemeasure to the boneyard and spend some time crawling around and measuring. If you find a driveshaft out of a car that's the correct length but the u-joint yokes are of a different size, you should be able to obtain a "crossover" u-joint from your local parts store. Hope this helps.

Regards,
Wannabe

howziit guy!

just got through measuring for a new HD driveshaft, for THE PINK LADY.

i now hold great respect for the simple tape measure, and the straight-edge ruler.

if you feel adventuresome, now's the time to pull the pinion yoke, and change that leaky seal...or upgrade to 1330/1350-series u-joints/yokes.

don't be afraid of removing the pinion yoke. it's as simple as pulling a harmonic balancer.

Myron,,,,, one may think it is easy, HOWEVER, many types of rear-ends are assembled with what is called a crush-sleeve.Once it has been crushed, it is nearly never that it is reuseable.
-Some have gotten lucky with just doing a proper retorque on the re-sassembly ofthe yoke to the rear-end.
CHeck with a reputable shop that services rear-ends and gear assemblies.

I have one of the Hollander books like the salvage yards use. I looked up drivelines for Chevy / GMC trucks.
The 117.5" wheelbase trucks use a #1260, 1973 - 1981, turbo 350, which is listed as 56-3/16" long.
#1272, '73-79, 4x4 w/fulltime transfer case,
57-7/8" long

These are the only ones close in the Chevy trucks. Some of the Dodges use a 58". but that would be a mess trying to adapt. Joe

howziit Mechainiac!

sorry, my bad. thanks for being kind enough, not to shoot me down.

i guess i'm speaking like an over-enthusiastic amateur... which i am.

i just removed my old pinion yoke, waiting for DENNY'S DRIVESHAFT to send me the 1350-series yoke.(he never emphasized worst-case scenario.)

should i just take a chance, and torque it on? what's the worst-case scenario?

i'll call the locals for an answer, but i wanted your unbiased opinion. sometimes i think the local shops want to scare me, into giving them my business.

sorry if i steered anybody wrong, about replacing the pinion yoke.

Thanks for the info Gents!

ChevyShelly, make sure you get a slip-yoke for your TH400 tranny as the ones from a TH350 will not fit.

Myron, I have more than enough knowledge to get me in trouble
I would say that after you torque the yoke nut, if you can pull the rear cover and look at the gear teeth contact patch(people who do this use a lead paint to do this)and it is within acceptable limits it should be fine.(you can look things up at the local library if you do not have books).
If things are not set up correctly, the gears can destroy themselves in a short time or it could go for a while and get worse with time(couple of weeks or a month or so).
There are critical measurements/settings such as pinion depth(set by using shims and the crush sleve on some rear-ends),then there is the bearing pre-load set by the torque on the pinion nut. Then there is the back-lash which is set either by shims (on some) or adjusters on either side of the two carrier bearing caps (which look like main-bearing caps in an engine).Then the carrier bearing caps need to be torqued to proper settings. After all that, the gear teeth contact area needs to be checked again to make sure it is in its proper spot so it will give you a long trouble free life
Read up on it a bit so you will have a getter understanding. It is not really hard to do,one just needs the proper tools and a lot of patience.

howziit Mechainiac!

thanks for the heads-up.

mine is a 9" **** rear end. i guess i could just remove the pumpkin, and have it checked at a local shop, right?

Sorry I never did answer Wannabe's question. The frame and motor mounts are original, I had to use a different crossmember for the tranny, still have whatever rearend that a 78 Chevy pickup would have had. Again I appreciate the response. Shelly

Oh yes and also Mechaniac, I have the yoke for the 400. I measured from the center of the cups on the u-joints with the yoke up on the tranny shaft and came up with the 58 "s. A buddy of mine told me I needed some clearance for when the motor torqed. In other words dont slide the yoke all the way up??? Oh yea I aint no mechanic

Shelley just get new one made or old one from parts truck shortened, have them balance and install new joints while apart. Call your driveshaft shop and ask how they want measured. Some can go by center to center on joint cups, some can go from other places. Best to have the yoke in trans to measure. You have to allow for movement in/out of yoke when you hit bumps and haul loads. You don't push yoke all the way in or pull way out. You can usually see the wear area on the yoke to see where it rides on seal most of time. Place it in same place on new trans. Replace the trans seal while down too. Doubt you would find a stock shaft, just what you want before going nuts looking or if at all. Call the shop, measure like they say, take one to them or they will have all the parts and tube if you got bigger bucks to spend! You can shorten, but you can't lengthen w/out buying a new tube.

hey Mechainiac!

the owner of the repair shop i sometimes use offered to set pinion preload(20 inch-pounds,he said).....for FREE, if i bring in the third member.

might just buy the torque wrench myself and do it myself, now that the shop owner explained it to me.