Gun Jam

I had that issue too. If an axle is bent enough to see it will cause hell.

I think runout tolerance is .002 max on either the face of the flange or the top. Pull the brake drum off and check the flange with a dial indicator on the edge and the face.

69mach1377

I'll need to get an indicator...thanks.
And with 143k miles on the original axle bearings, how long do they last?

barnett468

hi

well they last st least 143k miles i guess, lol.

some go more and some go less. they will growl when they are bad but with 143k on them they are not in the best of shape.

barnett468

easy deal, swap the wheel assemblies. id the left still wobbles it is a bent axle.

if the right then wobbles it is a bent rim or bad tire.

barnett468

i did not see if someone posted this but the factory pinion angle is 5 degrees or close to it. 4 is also fine meaning that if you lower your car 2" you do not need to change the pinion angle..

69mach1377

Pointing down or up?
I did swap them out and it looked a little better, so I went for a ride and the 80 mph vibe showed up as usual.
Not sure if I would hear a growl above the exhaust growl.
I'm wondering if the driveshaft is just not up to task going 80mph at 2200 rpm with my gears and tires.

barnett468

driveshaft runs uphill 4 to 5 degrees from the pinion.

you can get your shaft tested fir straightness.

the rear yoke might be bent a hair but you said your tire definitely wobbled on the left side so, that must be fixed first then tested before changing anything.

69mach1377

So that means the pinion angle is down compared to the shaft...mine is at 0* with a 2* shim, so it will be 2* down when I pull the shim out. The shim was tried to remove the vibe but it did not work.
I had my DS shortened, straitened and balanced in prep for the T5 swap and then rechecked for balance after the vibes showed up.
I'll get a dial indicator this week sometime and check stuff out next weekend.

Gun Jam

The trans should hang down say 3* and the diff should point up 3* so the DS would climb up from front to rear to meet the diff

racer_dave

Read through all this, and noticed a lot of people having questions about their driveshafts and getting them balanced. Coleman and FastShafts both make driveshafts for racing in 1/2 inch increments. You can source them from Lane Automotive, Port City, Lefthander, Jegs, Summit. I use Coleman's in my racecar and spin them to 7800RPM without issue. I've also used Fastshafts in my modified and spun it over 8000RPM. They aren't that expensive, maybe $300 tops. Which is probably not much more than you're paying a local shop.