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Yes another pinion angle question.

CaliXJ

NAXJA Forum User
Location
Oceanside, CA
Ok so i have read and read about this but kinda confused here.

91, AW4, NP231, 8.25 rear, 4.5 RC LA kit, IRO H-n-T W/ front shaft (4.5* shims)

Ok so i've had the lift and H-n-T installed for about 3 mo. with very min. vibs at Hwy speeds 60-65. To the point i wasn't worried about it. I've been out a few times to get things flexing and settled in and all was fine in tell last weekend. I notice on my way home it was a little worse. Vibes happen while on the gas and worse while off gas/coasting. So i hit the search function. My output shaft is 7*, DS is 15*, Pinion is 12* so i'm 3* lower than DS. I know some will ask " how do you know its rear DL vibes"?

I've been running a week with NO front DS and vibs are getting worse.
Checked ujoints-seem to be good.
Put front shaft to rear. (actually got a little worse) Front shaft is 19 yrs old. LOL
Pulled rear DS, installed front and drove in 4H. Vibes gone other than my hubs that need to be replaced. LOL

So even with a SYE and a crossmember that acts as a T-case drop do i still want 1-2* below DS? Can i get a 5* or 5.5* shim?

Thanks!
 
yes 1-2 is best. you said you had a front drive shaft in the back? hows the slip joint on it? my front just crapped out and it was vibrating so bad it loosened the pinion nut, all because that slip joint.

reset pinion and go from there.
 
yes 1-2 is best. you said you had a front drive shaft in the back? hows the slip joint on it? my front just crapped out and it was vibrating so bad it loosened the pinion nut, all because that slip joint.

reset pinion and go from there.

Well the DS that i have been running is one that i purchased from IRO with the Hack-n-Tap kit. No telling what kind of refurb those things actually go through.:dunno: I'll have to take it in to my local driveline shop for a once over to see what they say. As far as a local shop having 5* shims.. RRO is the only place i've seen so far.
 
If your vibration is getting worse, something is wearing out.

Check all the shaft joints and the slip yoke. Also, check the drive flange from the h/t kit. make sure it's still tight. Make sure the pinion nut hasn't walked out or the pinion bearing is loose. Also check the drive shaft and see if there is a bare spot/weld mark where a weight might have come off(might want to look at both shafts, since the vibration happens with both)

Edit: are you sure you cut the output shaft square? if the yoke is slightly crooked, the vibration isn't going away no matter what you do.
 
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If your vibration is getting worse, something is wearing out.

Check all the shaft joints and the slip yoke. Also, check the drive flange from the h/t kit. make sure it's still tight. Make sure the pinion nut hasn't walked out or the pinion bearing is loose. Also check the drive shaft and see if there is a bare spot/weld mark where a weight might have come off(might want to look at both shafts, since the vibration happens with both)

Edit: are you sure you cut the output shaft square? if the yoke is slightly crooked, the vibration isn't going away no matter what you do.

Yeah the Pinion nut and H-n-T yoke nut were things that i checked as well. Both tight. I did notice the CV on my DS sounds really dry when i move it and can't seem to figure out how to grease it? I see the plug type things in the ujoints but nothing for the ball and socket between the two. Any thoughts?
 
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