need help with drive line
 

I think that I may have had the drive line people cut my drive shaft too short, here are some photos, what do you guys think?

Re: need help with drive line
 

...is that crossmember bent??? That "lip" look's wrong...

Re: need help with drive line
 

as far as I can tell its not bent? by the way its a 66 c10 if that helps any.

Re: need help with drive line
 

they should have about 3/4" free play on the yokes. push the yoke forward until it stops and then pull back about 3/4" and that is where it should be.
ron

Re: need help with drive line
 

Looks like it should be a good inch or inch and a half further into the transmission but I've not fooled with one that has a 2 piece shaft and center support bearing.

Re: need help with drive line
 

actually the back of that trans does seem low or is it just an illusion.is the centre brg to high. it did mount downwards from that brkt off the crossmember did it not. the centre brg should be lower?????
ron

Re: need help with drive line
 

The back of the trans is lower.as far as the support bearing I'm not sure about the bracket it does appear to be high.
Posted via Mobile Device

Re: need help with drive line
 

Thats what I was thinking.

Re: need help with drive line
 

Your center bearing isnt mounted in orginal location.....whats the reason why you did this?

Re: need help with drive line
 

in the first 2 pics, it looks too short. When you provided the measurements, did the truck have weight on wheels? (actually that's a dumb question - if you did that, then your d/s would be too long... )

If you can raise the rear wheels off the ground and emulate full suspension travel - then look and see how much worse it looks - only option might be a new front shaft. If you still have sufficient engagement with full suspension travel, I wouldn't worry too much about it. BUT - if it's "iffy" I would get it fixed, you don't want that sucker droppin out and acting and earning your pole vaulter letterman's jacket when you least expect it...

EDIT - btw, if all the other questions folks are posing don't make any improvements if/when you make corrections, THEN consider what I wrote. For instance - if the tail of the trans is mounted too low, you will have less engagement than you normally would - same same regarding the crossmember mounted in the wrong spot, etc etc. Take a look at all those items first, and if you're still in the same predicament, I'd check engagement at full rear susp travel.

Re: need help with drive line
 

I think that it is the heavier one and has different mounting than the orig and was mickey moused into there
ron

Re: need help with drive line
 

the drive shaft wasnt in the truck when i got it so this is were i thought it was supposed to go, could you tell me or show me where it is supposed to go?

Re: need help with drive line
 

it hung off that brk on the back of the crosmember. see that bracket with the holes in it above the d/s
ron

Re: need help with drive line
 

The driveshaft and carrier bearing assembly you have now is superior to what brokenspoke is referring to. Just about everyone that has that whimpy carrier bearing hung from the top, has problems with them. I would definitely keep what you have, it is the heavy duty version.


As for the driveshaft length/engagement, it does look to me that the front shaft should be at least 1" longer. But that is also depending on how much engagement the yoke has with the trans output shaft. I also noticed that the rear of that trans appears to be quite a bit too low. The trans mount looks to be about even with the bottom of the frame. It should be a couple inches or so above it.

Re: need help with drive line
 

Heres a picture of how your original setup should look like(dont mind the drivline angle thats air bags deflated and ive since corrected the extreme angle) just look at the center carrier bearing:
http://i976.photobucket.com/albums/a...nnz/010-14.jpg

Ive also have read that the type with the bottom mounted carrier bearing like you have installed is a bigger driveline(1.3780",1.5748") then the style that hangs from the top(1.1811"), so if you were to switch to the right one for your year truck you would have to swap in a whole driveline and not just the different style bearing!
I agree with captain fab on that the bearings that hang from the top are crap, ive had three come apart(just pinch welded together) and finally had a buddy put a nice thick weld around the last one to make it work, they do sell a billet one that cost $100 but ive never used it, I would just keep the setup you have since it is a larger size drivline and a all around better bearing setup and would just have it remade longer.

you should be measuring with all the weight of the truck resting on the wheels, so if you can crawl under the truck and measure with out jacking the truck up that would be ideal, but if you have to jack the truck up make sure you have the jack stands placed under the axle and not on the frame allowing the axle to hang.

I believe you should only need to have the first piece of drive shaft coming off the trans remade not the whole thing, but i would double, triple check everything!
heres a link to measuring a two piece driveshaft:
http://www.actionmachineinc.com/mult...haftguide.aspx

and you might be able to bring the center carrier bearing down a bit if you remade the bracket its bolted to shorter, but you can probable get away with were its at now...and your cross member looks just like mine so i dont think its bent...

Re: need help with drive line
 

when i said bigger driveline in the other post i meant the shaft part that goes through the bearing, I dont know if the overall drivline is bigger or not.

also looking at your pictures again its hard to see if you not have a transmission mount in the back? if not i would get one and put it in it will help with the tailshaft being at so much of a angle,and id put it in before i had the driveshaft remade.

heres a idea if you wanted to lower the center bearing(if putting a trans mount in doesnt help the angle) is to bolt a piece of flat stock and bolt the bearing to it,might not have to go as low as i drew the line, you could use the stock photo of my driveline for reference to where the bearing is in relation to trailing arm bolts..... i drew a red line representing the piece of flat stock:
http://i976.photobucket.com/albums/a...berbearing.png

Re: need help with drive line
 

Thanks Captain Fab....this is a new one on me.....when did this revised support bearing take place?

Re: need help with drive line
 

It's hard to tell by the picture, but I was wondering, do you have any room for travel on the rear shaft? I don't see any splines showing. I would have to look again at mine but I believe i have at least an inch or more of splines showing. Curious if that is going to bottom out on you.

Not sure without measuring but could you make up the shortness by moving the position of your carrier bearing forward, giving you the necessary room for the rear shaft and moving the front shaft into the tailpiece an inch?

Re: need help with drive line
 

I dont think it was a "revised" carrier bearing i think it was old design used in the 60-62 x-frames and when gm switched to the ladder style frame from 63-66 they went with the hanging type carrier bearing....but i might be wrong captain fab might know for sure...

Re: need help with drive line
 

your right he is out of spline on that rear slip yoke( i enlarged the pic for a better look). that is the more important one for in the 2 piece setup for movement. if not it will pound the rubber cushion out of the centre support in no time. if that one is working properly then the frt shaft doesn't have to move as much. i would just section that centre mount to lower it to the same point in elevation that the orig was.
easy to raise that trans mount crossmember; just mount it on the top side of where it is and just space it up a bit. there could be another possibility why this looks that way. he frt motor mounts could be higher doing to the person who installed the eng. they may have installed later eng mounting, and some are a little higher than others. a lot of people just stick these things in these trucks and are not really aware of how things should be. they just stick it in. the centre line (axis) of your crankshaft should be on about a 3 degree drop from frt to back. but if you could put a level on your carb mounting flange(manifold), that should be level from frt to back.
ron

Re: need help with drive line
 

Ya raise tranny cross member 2in or so. add 2 to 2.5 in to rear shaft move carrier bearing forward an 1in or so. have to see measurements. ideally u want ujoint to be even with trailing arm pivot then u have no driveshaft plunge. and no more than 1in or yoke showing.

Re: need help with drive line
 

doesn't make sense. add 2-2 1/2" to rear shaft, move carrier brg forward 1". he is out of travel now on the slip yoke. how is it going to fit. what is it trying to accomplish by doing that
ron

Re: need help with drive line
 

Thanks guys you gave me some things to look at I will keep you informed. Buy the way this truck didn't come with this bearing set up? I thought the 1/2 ton had a bigger drive shaft than my c20 hince the bigger bearing. So which year truck had the bigger drive shaft and bearing.
Posted via Mobile Device

Re: need help with drive line
 

i think what he was getting at is the whole senerio needs to move towards the trans ,so the rear drive shaft( #2 piece) needs to be longer so the middle u-joint is at the same pivot as the trailing arm bolts pivot, so it pivots at at the same point which makes sense if you look at the photo i posted of the original style(right now theres two different pivot points), but if you do that the carrier bearing may need to move forward or it may not(would have to make a new crossmember for the bearing to move forward), then you would move the first driveshaft (#1 piece) forward into the trans ( but it might have to be shortened to gain back splines), and right now the trans looks to be hard mounted to the trans crossmember if he put the rubber mount inbetween the trans and crossmember it would correct some of angle the tail shaft has pointing down.

i dont know if you can use this setup in the hanging type frame ,now that i think about it in my old 65 and my 66 they both have a two piece driveshaft but not a slip yoke in the middle!
http://i976.photobucket.com/albums/a...erbearing2.png

Re: need help with drive line
 

even with the orig centre support the u-joint would have been behind the pivot point of the trailing arms. did the orig not have the u-joint yoke right at the centre support and the slip yoke run the other direction back towards the rear. this is more than likely a hodge podge of pieces put together.
ron