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71 CJ5 drivetrain blew up... what now?

Discussion in 'Early CJ5 and CJ6 Tech' started by JhnBrackett, Feb 16, 2010.

  1. JhnBrackett

    JhnBrackett Race Engimuneer

    Let me clarify, I SCREWED the pooch on this one. I was front wheel tow dollying my baby without the driveshaft disconnected. Vibrations happened and the transfer case popped into 4WD low while going 75 mph. Truck barely hiccuped but the oil spray and clutch fork bouncing down the road in my rear view mirror let me know something was amiss...

    Specs:
    71 Jeep CJ5
    Dauntless Buick V6 - rebuilt
    T-86 Transmission - rebuilt (ha ha ha... *tear*)
    Dana 18 T-case - rebuilt (ditto)
    Warn Overdrive - JUST installed prior to BOOM
    4.88 Axles w/ front disc

    The clutch fork bolts sheared, the rear driveshaft & e-brake drum splines are 3" too far back & slightly askew. Even the carb sheared in half... yeah...

    My assumption is that the tranny & t-case are crap. I've seen the various options available to swap in but looking for recommendations. I'd prefer not to tear both cases apart to replace random components and there are tons of Jeeps locally with assorted donor prospect. Stick with the current type of setup or upgrade the drivetrain too...?
     
  2. $ sink

    $ sink Gazillians of posts

    Dude... sorry to hear it.
     
  3. Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    WoW--ouch ouch ouch.. What type of driving. Is this just a week-ender joy rider or off-road a lot. How on earth did this cut the carb in half?
     
  4. Patrick

    Patrick Super Moderator Staff Member

    Wait...Clutch fork bolts?
    E brake drum splines?
    Never heard of these.

    Sheared the carb in half?

    We're going to need pics...
     
  5. Dummy

    Dummy I kick hippies

    Save the Warn for sure. Order the parts and do it yourself or send it off to Herm. I bet it can be salvaged.

    As long as your intermediate shaft in the Spicer 18 didn't spin in the case I bet that can be rebuilt too. Lots of take-out cases in really good shape kicking around on Willystech.com, here, there, everywhere.

    Hit the boneyard or craigslist and find a late '50s-early '60s 2WD Chevy pickup with an SM420. Gun the yoke off the back, order up a Novak PN 422 SM420-to-Spicer 18 adapter and score yourself a GM-pattern bellhousing and bolt that stuff together.

    Hopefully the 225 is still good. If not, rebuild it or replace it. Nothing like an odd-fire.

    Good luck and sorry for your troubles.
     
    Last edited: Feb 16, 2010
  6. JAlves

    JAlves Sponsor

    Sorry to hear of your mishap. Before you decide on the trans and transfer options, are you sure the engine is still good? The members will have a number of good options depending on your engine choice.

    And we definitely need pics!
     
  7. Jeepenstein

    Jeepenstein Me like Jeep.. 2024 Sponsor

    I second the motion for an SM-420 swap.... The D-18 and the warn OD can probably be saved with some careful rebuilding.

    BUBBA
     
  8. Long&Low

    Long&Low Active Member

    All I got is OUCH, man that stinks.
     
  9. AKCJ

    AKCJ Active Member

    Note to self - NEVER drive 75 while towing the Jeep. . . .

    Sorry to hear such bad news.

    Maybe you could explain the clutch fork bolts shearing thing? My clutch fork pivots on a ball stud and "forks" onto the throwout bearing on one end and has the cable on the other end (no bolts).

    We gotta see the pictures of the carb - that is just wild.

    I agree with dummy - you'll thank yourself for putting in the sm420.
     
  10. Glenn

    Glenn Kinda grumpy old man Staff Member

    Unless the transmission was in gear maybe it didn't get hurt...much? I think we're all having a tough time understanding the damage that happened. Unless you had the interlock pill out I can't imagine how it could have shifted into low, even then it seems impossible. Weird. :?
     
  11. JhnBrackett

    JhnBrackett Race Engimuneer

    http://public.fotki.com/jhnbrackett/jeep-cj5-damage-***/

    My apologies for the delay but it's been a tough Spring. Wrecked my only other working vehicle while the truck was getting a new transmission... installed by moi. Not my year thus far.

    Looks like I need a new carb, bellhousing, clutch fork and rear driveshaft ebrake internal components.

    Still not sure if all Buick V6-T14 housings interchange yet. Sounds like the one from a 71 is unique... dammit
    http://www.earlycj5.com/forums/showthread.php?t=61798

    Time to start scrounging for repair parts. Can't wait to get this thing back on the road, there's nothing like cruizin down the road with the doors off... *sigh*
     
  12. jayhawkclint

    jayhawkclint ΜΟΛΩΝ ΛΑΒΕ

    Oh lord...

    3spds and D18 are dime a dozen. If it were me, I'd score a cheap 3spd drivetrain to get it running again quickly, let the scars heal a little while you build up a 4spd.

    Post up some WTB ads in the classifieds section. Pretty sure I've still got a '71 bell laying around somewhere. Probably your e-brake parts, too.
     
  13. 80cj

    80cj Member

    Did the transfer case actually shift into low range or did the helical gear on the output shaft seize to the shaft? In neutral and low range that gear freewheels on the output shaft but is still in mesh with the intermmediate gear. I had a 64 CJ-6 that had that helical gear seize to the shaft while running in low range. I was driving less than 10 MPH on a muddy road and all of a sudden things locked up and the engine died. I was able to shift out of low range into neutral and back into 2WD. With the gear seized to the output shaft, I was able to drive home. I couldn't figured what happened until I got home and pulled the transfer case pan.
     
    Last edited: May 3, 2010
  14. garage gnome

    garage gnome ECJ5 welder

    :shock: The carb snapped!?!
     
  15. JhnBrackett

    JhnBrackett Race Engimuneer

    jayhawkclint: The 3spd & Tcase have already been rebuilt and I've attached an overdrive to it. Doesn't seem worth swapping in a whole new drivetrain & 4spd if those components are working. The 4.88s with the overdrive make driving a blast no matter what speed.

    80cj: the lever actually shifted into gear while being towed.

    willysscjmj: Yeah... my thoughts exactly!
     
  16. 80cj

    80cj Member

    This reminds me of a post I saw on another Jeeping forum a while back. Seems like this guy was towing a YJ behind a motor home. Something on the Jeep locked up causing one of the rear axles to break (C clip). He looked back in his mirror just in time to see a wheel with axle shaft attached flying down the freeway. By the time he stopped, the brake backing plate was ground down several inches from skidding on the pavement.
     
  17. dnb71R2

    dnb71R2 SuperDave 2023 Sponsor

    Even though it's about a 15 minute hassle on both ends of the trip, there's something to be said for disconnecting the rear drive shaft for flat towing. I will continue to do that.

    Shifting a Dana 18 into the neutral position can be misleading. There are still several gears engaged. In the case of a stock V6 single lever shifter, this includes the gear the turns the front drive shaft. Even if you have your hubs unlocked, your front axle is still turning while in neutral during flat tow.
     
  18. Dan66cj5

    Dan66cj5 Member

    Time for a 4 barrel :)
     
  19. lynn

    lynn Time machine / Early CJ5 HR Rep Staff Member

    John, somewhere out in my shed is a '71 bellhousing, the one with the molded in adapter for the T14, unique to V6 '71s.

    Yours for shipping, just let me know.

    Sorry to hear about the carnage. I'm sure you'll get it back together, good as new in short order.
     
  20. JeeperYJ

    JeeperYJ New Member

    I flat tow with my YJ. I don't disconnect the DS. Has this happen to anyone else?

    Thanks