Carrier bearing problem lowered truck !

[BCOWANWHEELS]

Guys i have a problem ! I have a 72 lwb chevy tk., its been lowered 5" front and 7" rear as low as you can go with springs only. Anyway about every 10k miles i broke a drive shaft carrier bearing in the long section between the top of the bearing and where it mounts. I have no vibrations when driving and it turns freely when up on jack stands. I have all new u-joints and the carrier bearing assy is national brand, u-joints are timken and i grease them every 2k miles. My engine is a stock 350 with a th350 turbo trans. I,am a old fella so i drive very reasonable not doing burnouts or hard starts. AnY help or tips on this matter will be greatly appreciated.
Regards
bob in tn.

P/s
i will post a picture of the broken carrier bearing latter today when i get it off. Sorry about the caps i have bad eyes & hard to see small type !

[my70chevyc10]

I had the same problem when i lowered my 70 swb c10. At first i thought it was the part then i asked my driveshaft guy and the first thing he asked me was if my truck was lowered. I said yes it was lowered 6in in the rear. He then explained to me that the driveshaft slides in and out of the trans when the rearend goes up and down.My truck being so low it was already hitting the back of the trans and when it did it would bend the shaft down and break the bearing. To solve the problem he installed a slip yoke on the back part of the shaft like they have on a 4wheel drive. It can now move2-4 inches in eather direction and i havent broken one yet. Total to have him replaced all yokes (someone had beat the hell out of them and the little clips didnt fit) all new heave duty u-joints new center bearing slip yoke balanced and painted all for the $175. anymou questions just ask we are here to help.

[jondancer]

Buy the billet one , it's great.
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[BCOWANWHEELS]

pulled everything apart "again" and also pulled another driveline out of a parts truck, I swaped all the new U-joints and got a new hanger bearing "again". alls done except for installing it. i blasted and painted the 2 shafts while I had them apart and gave em a good paint job. going to reasemble the shaft assy monday. gonna give the slip yoke for the rear shaft some thought. I also was considering moving "up" the mount for the hanger bearing to re-gain what was lost in driveline angle. I think I can get 2" of more up. I also read there is a front and back on these hanger bearings. the side with the most rubber supporting the bearing goes towards the trans.
bob

[70jnktrk]

Same thing here a while ago..did my ECE 4/6 drop and after a few hundred miles the mounting area on top separated..see pic....tacked that back together and figured I was in for more trouble..see pic...talked to my drive shaft guy and after 'splaining' everything to me and talking about a slip yoke, he had me measure the distance from the 400 tranny to the third member..apparently it was within his limits and we just made a single DS...I removed the whole carrier assembly..smooth as silk....there are limits however to the total length that will work...hope this helps...

[BCOWANWHEELS]

Thats exactly where mine broke 2 times. I,d love a 1 piece d/shaft. Is your truck a lwb ? 1/2 ton ?

[70jnktrk]

Yep..1970 lwb fleetside...C-10..six lug...I put the 350 and the 400 tranny in her in 1991...good old truck..

[bajaracing]

i had the same problem on my c10., went thru two carriers within 6 months. This solved the problem for me..

http://67-72chevytrucks.com/vboard/s...d.php?t=384817

[BCOWANWHEELS]

Looks like i have more work to do..... I think I,am gonna make a girdle so to speak to reinforce this flimsey bearing mount out of 1/8" u.s.a. steel gonna start a design once i get my truck back on the road tomarrow, its a d/d for me. I,am very thankful for all of you fellas help...
Bob

[badfiero]

I thought you should know making a brace on both sides from the mount plate to the bushing part works. I used to replace mine every six months last one 5 years.

[Indyuke]

Also, the carrier bearing should be "set" with the truck ground. If it's set and tightened down with the truck in the air, the rear wheels are extended and pulling the driveshaft. That's fine, but when you place the truck back on the ground, it pushes the driveshaft forward again putting pressure on the carrier bearing.

You need to put the truck on the ground with the carrier bearing loose, bounce up and down in the back a few times, then tighten it. It will be in it's neutral spot then. I have 5 years on a replacement bearing assembly and it's still going strong.

[BCOWANWHEELS]

WELL I studied about this from friday evenning till monday evenning and decided to install a slip yoke in the rear drive shaft and I,am going to also build a girdle to support the carrier bearing. will have some pictures soon. I want to be able to go to any auto parts store and buy a carrier bearing assy. i have a desgn that will completely support the c/b assy. and bolt on in the top 2 mounting bolt holes so no modificatons needed to tk. or c/b. also "if" c/b does break it will support it until you can get home and not flop around.
bob

[prophetshrek]

I've also heard of people using a one piece drive shaft. I have had the same problem too. But I'm going to try billet next.

[BCOWANWHEELS]

Well got the slip yoke rear shaft in and the next week my trans went out ! Guess the vibes from the hanger bearing went thru my trans and hurt somethine inside. Got me anyther th350 but havent got it in yet. Its cold in the shop !