Will my drive shaft hold up?

lilbowtie

lilbowtie

Comic Book Super Hero
Jan 7, 2006
2,660
113
Canton Mi
Can I consider my driveshaft to be good enough?? Or should I look for a replacement??
As I have told people - do your homework! it's about the length of the shaft and the RPM as shown on the chart I posted. DRIVE SHAFT CRITICAL RPM

Critical Speed is the RPM at which the driveshaft is computer projected to bend or whip. Exceeding Critical Speed can produce vibrations that can result in driveshaft failure.
The vibrations can also cause damage to the differential gears and bearings. The transmission extension housing, along with the torque converter and planetary gears can also be destroyed.
When you take a small piece of steel and bend it repeatedly, the stress will eventually break the steel. The same effect occurs on your complete driveline when no attention is paid to Critical Speed.
 
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Kra5379

Kra5379

Not-quite-so-new-guy
Apr 30, 2019
16
3
Back in around 1996 I had an 82 Cutlass Supreme with a mildly built 403 (ported/polished edelbrock heads, mild cam,etc) i had a 350TH trans with a shift kit, but the car was an original V6 car with the 7.5" rear end, being that I was about 17 years old at that time i wanted the car back together on the street asap and couldn't be bothered with details like rear ends and driveshafts, I knew that I was asking for trouble with the 7.5" rear end but what I never expected was that not even a week into driving it, and while doing brake torque #15-20 in front of a buddies one night, as soon as i hit the gas and the tires started to smoke, i heard something loud and crashing, the tires stopped spinning and the car wouldn't move...as soon as I crawled under it to check it out i seen that the stock driveshaft had been twisted right in the middle, like it was an empty beer can and just snapped. That engine made approximately 375HP and just under 500lb/ft of torque. Moral of the story, with what you have invested into it, just get rid of the stock driveshaft and have a reputable driveline specialist make you a custom 3-4" aluminum shaft
 
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gnvair

gnvair

Master Mechanic
Sep 1, 2018
323
43
Southern New Jersey near Philly
But the 200 is a garbage transmission to begin with, especially compared to the 700R4, plus im pretty sure that the 200 is only designed/built to handle up to about 250-300HP and low torque
No more garbage than a 700r4/4L60E which have incurable weaknesses such as the weak *ss sun shells. The 83-87 Turbo Buicks came with 2004r's and there are quite a few of the Buick guys that put 800+ horses through theirs. There are a hell of a lot more performance items (i.e. billet input, billet forward drum, billet od planet, etc) as well a trans brakes available for 2004r's. I belong to several other message boards for F bodies, Impalas, etc and all those guys ever do is cry that their transmissions crapped out for the 2nd, 3rd, 4th times. I suppose there is a reason why the Turbo Buick guys don't go to the trouble to swap a 700r4 or a 4L60E into their cars ;)
 
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olds307 and 403

olds307 and 403

Comic Book Super Hero
Oct 14, 2008
4,963
113
Melville,Saskatchewan
The 2004R can be a tricky trans to get right and needs hard part upgrades to live. That being said, the 700R4/4L60-70E is a piece of crap. Don't forget the constant 3-4 clutch pack failures. GM still offers a warranty transmission because of it. Too bad the 4L80E didn't offer a little better first and deeper OD but it was designed to live behind big power where less gear multiplication is neccessary.
 
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M

Malibu795

Not-quite-so-new-guy
May 13, 2019
39
18
The 2004R can be a tricky trans to get right and needs hard part upgrades to live. That being said, the 700R4/4L60-70E is a piece of crap. Don't forget the constant 3-4 clutch pack failures. GM still offers a warranty transmission because of it. Too bad the 4L80E didn't offer a little better first and deeper OD but it was designed to live behind big power where less gear multiplication is neccessary.
can get lower ratios.. I know rossler sells up to 2.97/1.57 gear sets for 1st/2nd, think TCI and Hughes have gear ratios options as well
 
M

Malibu795

Not-quite-so-new-guy
May 13, 2019
39
18
Also.. running a lock-up trans pending TQ availability can run higher stall TC to offset taller gears
 
I

icr242005

Not-quite-so-new-guy
Mar 3, 2018
37
8
Learned my lesson the hard way last week. 383, 500HP, all new rear ended, built th350 trans, stock drive shaft Been doing some hits on the back roads with no problem. Bought MT ET Street SS and this is what happened the first time out with new tires. Cost of repairs. $100 new muffler, $100 bucks for exhaust repair, possible new tire $180 bucks, $60 dollars new yoke, 150 bucks for new tail shaft (hopefully trans is good internally) 75 bucks for new D loop, 70 dollar tow , 1 new pair of boxers priceless. I’m lucky that I had no injuries. The price difference between a .125 wall aluminum driveshaft and a steel driveshaft is NOT enough to worry about. Stock driveshafts belong on a all stock car. Knoxville drive line in Knoxville TN are some great guys to deal with. Good luck. BTW make sure u have a rev limiter on ur car cause when sh*t breaks, not enough time to take foot of pedal.
Learned my lesson the hard way last week. 383, 500HP, all new rear ended, built th350 trans, stock drive shaft Been doing some hits on the back roads with no problem. Bought MT ET Street SS and this is what happened the first time out with new tires. Cost of repairs. $100 new muffler, $100 bucks for exhaust repair, possible new tire $180 bucks, $60 dollars new yoke, 150 bucks for new tail shaft (hopefully trans is good internally) 75 bucks for new D loop, 70 dollar tow , 1 new pair of boxers priceless. I’m lucky that I had no injuries. The price difference between a .125 wall aluminum driveshaft and a steel driveshaft is NOT enough to worry about. Stock driveshafts belong on a all stock car. Knoxville drive line in Knoxville TN are some great guys to deal with. Good luck. BTW make sure u have a rev limiter on ur car cause when sh*t breaks, not enough time to take foot of pedal.
updated cost. Add about $300 buck for ER visit when trans slips off jack
 

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