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I'd hit it
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62 Posts
Discussion Starter · #1 ·
Alright...haven't dyno'ed yet...but I am defintely puttin some horse to the wheels(maybe 420 to 470 at the wheels). I have posted here before about breaking a driveshaft in half when I stomped on it at 10MPH coast. I know, sounds impossible...well believe. My wallet sure had to accept it. Well...from there...
1. New driveshaft...new yokes...all SpicerXL stuff...heavy duty and BALANCED.
2. Replaced adapter plate between T-case and 4L60e...had small crack in it
3. Drove home and the truck shook like a 7.0 earthquake at anything near or above 60MPH. No way get past 70MPH.
4. Bent output shaft in the NP246 T-case
5. Replaced with new NP246(cheaper than repair) and replaced the yoke, it was damaged from the output shaft
6. Still vibrating...no where near as bad but pretty heavy between 70 and 80 MPH
7. Rebalanced shaft...still vibrating.
8. Replaced rear yoke bearing and checked R&P gear and Eaton...everything good.
9. Still vibrating Btween 70 and 80...but getting better.
10. Just finished breaking down the 4l60E...put shaft on speed lathe...checked everything (all hardened parts), thrust bearings, planetaries...everything... checks out okay.

I am at a loss. The vibration is hardly noticable with no throttle, if noticable at all. It is only under accleration or just cruising throttle. And it is specifically only between the speeds of 70 to 80 MPH. Anybody? anybody? anybody? I'll take all guesses...it's just that it can be controlled via throttle that has me lost...I was sure it was in that 4L60E. :think:
 

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Drive It Like Ya Stole It
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6,656 Posts
well if ya happen to need another 246 I got one ill sell ya :crazy:
 

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I'd hit it
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62 Posts
Discussion Starter · #3 ·
well if ya happen to need another 246 I got one ill sell ya
Shweet....I guess...hope the 246 that's in there now stays happy. But I'll definitely remember that when the time comes.
 
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