80 Series turn radius adjustment? (1 Viewer)

[RivMan]

Hey folks.

I currently have two 80-Series that I drive regularly. They have very different turning radiuses. I initialy thought it was due to wheel offsets, however I swapped wheels around and the radius is still noticeably different.

Is there some sort of adjustment, or year-by-year change that modifies that?

80-Series #1 (Very tight turning radius):
1997 FZJ80
Formerly owned by @dogfishlake
Axles have been gone though, RCV shafts, part time kit installed
Stock radius arms with adjustment plates
Stock steering box

80-Series #2 (Noticeably wider turning radius):
1991 LSJ80
Formerly owned by @Stoshu
Axles have been replaced with 1994 FZJ axles
Axles have been gone through recently, stock shafts, part time kit installed
Delta 3" radius arms
Redhead / 105 upgraded steering box

Thanks
-Rob

 

[jonheld]

The only thing that would effect turning radius are the steering stops on each steering knuckle, assuming the wheelbase hasn't changed and there are no diffs that are locked.

 

[Broski]

There should be no change year model two year model.
Of the three that I have worked on, I came up with 95/8” of total travel on the tie rod. meaning clamping a square to the bottom of your axle housing turn all the way to the right, mark the tire rod, then turn all the way to the left mark to tie rod again.
Distance should be 9 5/8”
Things to check, there’s a a center alignment, Mark on the sector, shaft and Pitman arm.
If these are not lined up correctly. You will lose turning radius in one direction.
I would also check to see if your steering stops or hitting equally. One in the front and the opposite one in the back should be hitting at the same time. and vice versa when you turn the opposite way.

 

[Broski]

The only thing that would effect turning radius are the steering stops on each steering knuckle, assuming the wheelbase hasn't changed and there are no diffs that are locked.

The sector shaft to steering arm alignment could be off

 

[jonheld]

The sector shaft to steering arm alignment could be off

That would only effect 1 direction. The OP didn't specify.

 

[RivMan]

Thanks, guys.

I'll check out those stops. The steering does seem equally bad in both directions.

Thank you
-Rob

 

[Stoshu]

Rob - The steering stops were all adjusted on the 1991 LSJ80 when the last alignment was performed before to our Alaska trip this summer. They were all mismatched prior to the alignment and were not effectively limiting the steering travel at full lock, as designed. This is most likely where the difference exists between the two trucks. Perhaps I adjusted them a bit too much on the "conservative side" to limit potential steering component damage.

 

[jonheld]

Thanks, guys.

I'll check out those stops. The steering does seem equally bad in both directions.

Thank you
-Rob

From the FSM:

 

[Marvelicious]

I'm just speculating here, but does anyone else think the part time kit could have an effect? The limited slip center diff doesn't bind like it would locked up, but it still has to make some drag when turning tight, right?

 

[robnicko]

My thoughts are the LS one with 3" radius arms obviously has some decent lift in play which would alter the wheelbase geometry therefore affecting the turning circle. But with an LS just press the pedal a bit and donut it?

 

[RivMan]

Rob - The steering stops were all adjusted on the 1991 LSJ80 when the last alignment was performed before to our Alaska trip this summer. They were all mismatched prior to the alignment and were not effectively limiting the steering travel at full lock, as designed. This is most likely where the difference exists between the two trucks. Perhaps I adjusted them a bit too much on the "conservative side" to limit potential steering component damage.

Great info! I suspect that's where the disconnect is.

From the FSM:

View attachment 3506931

Perfect, thank you!

I'm just speculating here, but does anyone else think the part time kit could have an effect? The limited slip center diff doesn't bind like it would locked up, but it still has to make some drag when turning tight, right?

Both trucks are part time.

My thoughts are the LS one with 3" radius arms obviously has some decent lift in play which would alter the wheelbase geometry therefore affecting the turning circle. But with an LS just press the pedal a bit and donut it?

Both trucks are lifted about the same amount. It does do great donuts though!

Thanks!
-Rob

 

[CharlieS]

Nice rigs!

 

[Marvelicious]

Both trucks are part time.

Ah, so they are... One of these days I'll learn to read things completely when browsing on my phone (no I won't!).