Driveline angle question

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243
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Driveline angle question

Post by 243 »

I hope the rest of the day goes as smooth as the test fit. The Yukon transmission mount is almost centered on the Jeep crossmember in the stock location, two holes, done, I hope :D

The transmission output shaft is sitting at 3 degrees down, and the pinion 6 degrees up. I would prefer not changing the Yukon mount or lowering the crossmember. However, I also don't know if there will be a clearance issue between the body and the transmission requiring I lower the transmission.

Do I need to fine tune the driveline angle now or wait until everything is bolted together and with a full load?

My though is a pair of 3 degree shims would be easy to add later.

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1978 Cherokee NT, 5.3/4L60/NP241 in Progress

cmaje72
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Re: Driveline angle question

Post by cmaje72 »

Thats exactly how I did mine at 3* on my 79. You should be good especially if you are using fresh body mounts. There is a heat shield on mine that I had to clearance about 1/2" for the tcase since I clocked it almost flat. Couple whacks with the jeep hammer took care of it.
As far as the rear axle goes you should really set its angle after you have the full weight of the body on it. Are you using a centered rear or the offset QT rear?
79 Cherokee 5.3/4l65E/NP241C
79 CJ7
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Re: Driveline angle question

Post by 243 »

Centered, it came with the GW I parted for the chassis.
1978 Cherokee NT, 5.3/4L60/NP241 in Progress
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Stuka
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Re: Driveline angle question

Post by Stuka »

You could just run a CV on the transmission side and not worry about the angles being different at all. The angles being different only matters if you have u-joints on both sides.
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Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

cmaje72
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Re: Driveline angle question

Post by cmaje72 »

You could run a CV shaft but you would still have to reset the rear axle angle to point at the tcase output. That also assumes that one would convert the tcase to a fixed yolk and get the proper flange.
I am still running a slip yolk, the offset qtrack axle, and a rear driveshaft from a 91 2 door s10 blazer (which incidentally fit perfectly with no mods). I thought it would have tons of vibes from the wacky angles with the qtrac axle but its not too bad. All of this will get rectified when I do my axle swap this winter though.
79 Cherokee 5.3/4l65E/NP241C
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babywag
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Re: Driveline angle question

Post by babywag »

Why not adjust engine mounts to set rear trans. angle that way?
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Re: Driveline angle question

Post by rocklaurence »

Dont do anything until the weight is on the axles.

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Re: Driveline angle question

Post by sonoraed »

rocklaurence wrote:Dont do anything until the weight is on the axles.
Yup good advise, Tom Woods driveline website contains some good info concerning driveline angles
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