Driveshaft concerns/questions

[Sport/Truck]

I was under the truck today (luckily) and noticed my center bearing is going out.
I'm wondering what direction I should take this project now, and would like pro's & con's for both one-piece or two-piece driveshafts.

The truck is lowered, but would like to lower it a bit more so it will equal a 4, 6 drop (no air bags).
I'm leaning towards a 700r4 or 200r4 trans for a future upgrade also.

The thing that bugs me about the two piece, is it seems built wrong with no sip yoke. And from what I remember reading here this is completely normal. (Probably why center bearing is going out?) So if I keep this setup I'd like some input as to how I can upgrade it to include a slip yoke.

So share your thoughts and Ideas to why one is better than the other.

[69 longhorn]

On a shortbed truck, you should be able to run a 1 pc shaft, without lenght issues(longbed trucks push that 71" rule on the shaft). The 1 pc shaft is generally built with larger diameter tubing, so you do need to check that you have clearance through the crossmember on your lowered truck for your full range of suspension best of luck,crazyAL.

[scrapmetalart]

replace the u joints, carrier bearing & add a slip joint & not have any more problems.

[Andy4639]

I took the drive shaft out when I installed the 700-R4 back in 1990. I had it shortened and new bearings and carrier installed. Last year I had the carrier done again it wore out. I have a long bed so it a most on mine.

[Sport/Truck]

Originally Posted by scrapmetalart

replace the u joints, carrier bearing & add a slip joint & not have any more problems.

How did you do your slip joint? near the center or at the rear end?
Ware did you get your parts? Used?

If I do the two piece I'm going to use the Inland Empire center bearing.

[GASWAGON]

CPP sell the rear shaft new with a slip yoke built in. I think I paid 199.00? get the urethane carrier bearing and put new joints in the front and have the whole thing balanced.

[Andy4639]

For the price of that Carrier bearing I had the drive shaft re built with new bearings and carrier and balanced. The first one lasted almost 20 years so it was a no brainer for me.

[grs]

I dropped my truck 4 inches in the rear. I put a one piece drive shaft in it. I removed the piece that the center bearing bolts to. I have a short bed.

[GASWAGON]

Originally Posted by Andy4639

For the price of that Carrier bearing I had the drive shaft re built with new bearings and carrier and balanced. The first one lasted almost 20 years so it was a no brainer for me.

The price is for the new slip yoke drive shaft. The bearing is extra. You may have "fixed"the problem, but not the cause of the problem. Not using a slip yoke will also add extra load on the pinion bearings in the rear end and the tail shaft bushing and thrust wsashers on your 700r4. At factory height, it's not a problem because it is only momentary that the load is applied during suspension travel. A lowered truck is constantly exerting these forces on the drivetrain. As the suspension travels up the distance is shortend between the trans and differential. Hope this helps J.

[Andy4639]

I have had this drive shaft and transmission in the truck for close to 20 years. I wasn't awear of any problems with it. The drive shaft was shorten when I first installed it. I haven't had one problem with the stock rear end which is the orignal one except for brake shoes and wheel cyclinders.
As far as added wear I think not.
The two peice shaft was built with 350's 400 turbo and no problems. I can't figure out your concern. The drive shaft rear section follows the travel the front stay's the same always no matter what trans you have.

[cdowns]

i'd drive the truck to a driveshaft shop and ask them for thier best advise and a price quote

[GASWAGON]

Originally Posted by Andy4639

I have had this drive shaft and transmission in the truck for close to 20 years. I wasn't awear of any problems with it. The drive shaft was shorten when I first installed it. I haven't had one problem with the stock rear end which is the orignal one except for brake shoes and wheel cyclinders.
As far as added wear I think not.
The two peice shaft was built with 350's 400 turbo and no problems. I can't figure out your concern. The drive shaft rear section follows the travel the front stay's the same always no matter what trans you have.

I'm not concerned. I was only trying to help give the correct info. From your answer I can tell you don't understand. As the rear moves up, the distance is shortened. So therfore the shaft has to move foward. the slip yoke would take up the shortened distance. The factory non-slip yoke driveshaft,can't absorb the change and just shoves the driveshaft centerbearing foward trying to push the rubber mount out of the retainer strap. It also loads the bearing on the rear side wich it isn't designed to handle, causing the premature wear. So if your truck is lowered there is a constant pressure applied. I wasn't trying to wind you up, I relize these are things most don't think about,but I was just trying to bring my experience and engineering background to the table to help. Cdowns is right any competent driveshaft shop will tell you the same. J

[Andy4639]

GASWAGON,
From your answer I can tell you don't understand.

I don't understand is correct. Why do you want to insult me?

I just stated what I had done. Mine lasted 20 years like I said. I drive it everyday. I have drove it over 200,000 miles like this and no problems. Yes it's lowered and the shaft was cut per this. Yes a professional shop did it. One of the top shops in the upstate. Is it the perfect setup maybe, mabe not but for 20 years it's been OK.
Just a ?
When a stock ride truck hit's pot holes and such what happens to the same drive shaft?

[GASWAGON]

Originally Posted by Andy4639

I don't understand is correct. Why do you want to insult me?

I just stated what I had done. Mine lasted 20 years like I said. I drive it everyday. I have drove it over 200,000 miles like this and no problems. Yes it's lowered and the shaft was cut per this. Yes a professional shop did it. One of the top shops in the upstate. Is it the perfect setup maybe, mabe not but for 20 years it's been OK.
Just a ?
When a stock ride truck hit's pot holes and such what happens to the same drive shaft?

I don't feel I insulted you. Since you feel this way I appolagize. I just stated that I believe You don't understand. I explained this and answered your pot hole question. You put your 2cents in about what I had written and I responded. I don't see any need to discuss this further. Again, I'm sorry I hurt your feelings. J

[Sport/Truck]

Originally Posted by GASWAGON

At factory height, it's not a problem because it is only momentary that the load is applied during suspension travel. A lowered truck is constantly exerting these forces on the drivetrain. As the suspension travels up the distance is shortend between the trans and differential. Hope this helps J.

Originally Posted by Andy4639

The drive shaft was shorten when I first installed it. I haven't had one problem with the stock rear end which is the orignal one except for brake shoes and wheel cyclinders.

I think you're both correct, Andy having a shortened drive shaft mimics the same angle as the stock setup?

Seems a slip yolk would eliminate any stress on the carrier bearing. But having the proper length drive shaft is a must. I'm willing to bet mine is original- but my truck isn't all that low either.
If I'm going to spend time / money to fix it, I'd like to keep my future plans in mind and do it correct.

[grs]

Am I the only one with a one piece drive shaft?

[red71cheyenne]

I have one too. When I went to 700r4 I went to a one piece driveshaft. No problems, other than when I am loaded down. Potholes make it rub on the center support just so long as the bounce lasts. Hasn't caused any problems yet and its been in there for 10 years. Not so many miles on it, but its made two cross country trips like that. I was happy to get rid of the carrier bearing as it was just something else that could break.

[69 longhorn]

Originally Posted by cdowns

i'd drive the truck to a driveshaft shop and ask them for thier best advise and a price quote

Ditto.....

[grs]

Hey Red71, and all. Remove the bracket that the carrier bearing bolts to. It bolts to the carrier support. My truck is lowered 4 inches in the rear. See pic.

[scrapmetalart]

Originally Posted by Sport/Truck

How did you do your slip joint? near the center or at the rear end?
Ware did you get your parts? Used?

If I do the two piece I'm going to use the Inland Empire center bearing.

My driveline shop told me about $200 to install a slip joint. I havent looked into used ones as of yet.

[BB72CHEVKT]

I have a one pice in a short bed and one in a long bed. No probs with either one.

[scrapmetalart]

anyone know what cars or trucks a slip joint can be taken fom & added to our driveshafts?

[brad_man_72]

I wouldn't recommend a used slip setup, but I'm sure a front shaft for a 4x4 would be agood way to get close to the same small diameter shaft. This is not a project for the do it yourselfer and needs to be properly ballanced.
please don't spend the money on a billet poly carrier bearing! A properly built driveshaft will last a long time with a cheap carrier bearing.

[Sport/Truck]

Are the one piece units modified from a used shaft? Or are you having them made new at the driveline shops?
The one piece shafts require a slip yoke?

[brad_man_72]

I work in a driveline shop so I build new. You can modify a used shaft. Definitely work for a professional and ballance.

unless you are using a transmission with a bolt on yoke (you can use a slip trans yoke on these transmissions) or use bolt on yoke and have a slip and stub installed at trans end of shaft. The trans yoke provides more than enough slip for suspension travel, and you can't have more than 1 slip in a one piece driveline. It will fall out.