3 Speed Manual Shudder / Wheel hop in Reverse and First

[302fix]

Hello all.
I have a 1970 Bronco with 3 speed manual. 3.5" lift, 302, Sniper EFI, T shift.
Rig has been running great this summer but just started experiencing difficulties trying to take off in first gear and when I am in reverse.
I get significant shudder/wheel hopping and shakes so bad I can even get it rolling. Reverse has the same type inconsistent engagement but not nearly as bad. If I start out in second it is smooth. Once I'm rolling 2nd and 3rd run well, no issues.
Right before all these symptoms appeared there was a day where I couldn't shift at all and ended up disengaging the linkage and moving it manually then hooking the linkage back up.

I suspect that I'm having clutch or transmission lever adjustment issues. Very little play in the clutch from resting position.

I was pretty sure it wasn't driveline related but never did shim my rear end or get longer drive shafts after my 3.5 lift, so recently I did those tasks.
6 degree shims
new drive shafts

I'm thinking of taking a much closer look at linkage adjustments but suspect I am in for a new clutch.
2 kids in college so AX15 will need to wait.

Many thanks for helping me diagnose my next steps. Any suggestion on where to go next are most appreciated.

 

[Broncobowsher]

Look over the clutch linkage (pivot bushings)
Body mounts, motor and transmission mounts.
Others will point at other things as well.

Broncos are bad about clutch chatter if things are not right. Plenty of little things outside the clutch/transmission that are easy/cheap. Hard part is finding them, which one is bad and causing it. And often there are multiple bad things as stuff wears and ages.

 

[doran4x]

Glazed or cracked flywheel.


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[NC_Pinz]

Mine has been doing it for years. Flywheel has been resurfaced, different clutch plate and pressure plate, pivots checked, etc. Nothing seems to fix it so we've lived with it all these years. I've learned to feather the clutch to mitigate it. One day I'll go back to an auto.

 

[m_m70]

Fought this for a long time....After changing out the clutch and flywheel and still getting bad chatter, I changed the bushings and felts at the z bar and haven't had anymore issues in years. Just a thought.

 

[bmc69]

I've seen "rounded over" spring perches cause a lot of shudder during takeoff from a stop. Something to check for...

 

[67sport]

So this plagued me on my 67 for a few years. Tried all the things suggested here, added Duff traction bars, it sucked. I wheel hopped across every intersection. I'd let others drive it, no one could feather the clutch enough to avoid it.
When I pulled my small bearing rear to replace it with a big bearing, i realized the the center pin on the spring pack was a little longer than the hole in the perch. Evident by the witness marks on both pieces. The issue went away with the different rear end, as one would expect.
It may not be the cause of your issue given how yours started, but maybe it will help someone out reading this thread.

 

[69broncoMA]

So this plagued me on my 67 for a few years. Tried all the things suggested here, added Duff traction bars, it sucked. I wheel hopped across every intersection. I'd let others drive it, no one could feather the clutch enough to avoid it.
When I pulled my small bearing rear to replace it with a big bearing, i realized the the center pin on the spring pack was a little longer than the hole in the perch. Evident by the witness marks on both pieces. The issue went away with the different rear end, as one would expect.
It may not be the cause of your issue given how yours started, but maybe it will help someone out reading this thread.

So I have been experiencing chatter also and Im suspecting my its my trac lok rear end causing the issue. Either that or my transfer case. Im curious if you are or were using a stock Trac loc rear end? I have this loose clunk feeling that seems to start at the same time the as the chatter starts. It my chatter issue only begins when the drivetrain is warmed up. Im wondering if I have some sort of binding when things get warmed up that isnt there when cold.

 

[302fix]

Fought this for a long time....After changing out the clutch and flywheel and still getting bad chatter, I changed the bushings and felts at the z bar and haven't had anymore issues in years. Just a thought.

In my mind this seems like the next logical (cheapest) thing to get after. Since both first and reverse have the similar symptoms it would seem like the bar is not allowing complete engagement for either.

 

[302fix]

So this plagued me on my 67 for a few years. Tried all the things suggested here, added Duff traction bars, it sucked. I wheel hopped across every intersection. I'd let others drive it, no one could feather the clutch enough to avoid it.
When I pulled my small bearing rear to replace it with a big bearing, i realized the the center pin on the spring pack was a little longer than the hole in the perch. Evident by the witness marks on both pieces. The issue went away with the different rear end, as one would expect.
It may not be the cause of your issue given how yours started, but maybe it will help someone out reading this thread.

Thanks. I have new center pin with the 6 degree shim install and made sure it was properly seated in the perch which took some convincing.

 

[67sport]

So I have been experiencing chatter also and Im suspecting my its my trac lok rear end causing the issue. Either that or my transfer case. Im curious if you are or were using a stock Trac loc rear end? I have this loose clunk feeling that seems to start at the same time the as the chatter starts. It my chatter issue only begins when the drivetrain is warmed up. Im wondering if I have some sort of binding when things get warmed up that isnt there when cold.

The rear end was a small bearing open with 4.10s. Sold it and the 30 to a guy with a little Suzuki if I remember correctly.