Builds 1979 FJ40 Preservation-ish Project (2 Viewers)

[cruisermatt]

Make sure you account for spring center pin length if you’re going to add a spacer.

 

[locklaw]

Swopping springs left to right often fixes lean. Weirdly enough, you sometimes need to swop the rear pack to straighten the front, so there is no silver bullet method, but you'll probably want to start swopping the front packs first.

 

[pb4ugo]

I tried swapping rear springs to cure the lean once.

 

[OPMACHINE]

Swapping the springs seems like a plausible solution. The rear spring rates don’t seem to be even. I can’t see how the drivers side could be that much heavier, with the tire removed.

This is with a 3/8” spacer on the rear passenger.

Spring hangers angles :

 

[locklaw]

Swapping the springs seems like a plausible solution. The rear spring rates don’t seem to be even. I can’t see how the drivers side could be that much heavier, with the tire removed.

This is with a 3/8” spacer on the rear passenger.

Spring hangers angles :
View attachment 3264603View attachment 3264604View attachment 3264605

Never measure from the ground, measure from the lower centre lip of the rim straight up through the centre of the hub to the fender edge. This negates tyre pressures, sizing issues from manufacturers, etc.

Emu blades have "-", "0" or "+" markings like Toyota uses on new 70's, and you can play with these packs to level it depending on weight bias, tyre carriers, etc. Not sure about the Dobinsons you are using.

With that said and the distinct shackle angle differences you have, I would instead of a spacer add a leaf to the LHS (driver) side. Add it third from the top. You want the driver's side to be 5mm higher than the passenger side to account for driver's weight so you have a level vehicle while driving.

 

[middlecalf]

a few more pounds of air in the driver’s side rear tire will help

 

[pb4ugo]

I tried swapping rear springs to cure the lean once.

I found it was a waist of time. My results didn't make a difference. Hopefully it will work for you.

I've never understood the concept of lowering an offroad vehicle in an attempt to level it side to side.

 

[OPMACHINE]

Measured from lower lip of rim thru the center of the hub:

I am running 22psi in both rear tires.

I added a leaf to each pack in the rear at the same time I added the 3/8” spacer. Helper spring just make it stiff. Shocking it know! The Dobinson heavy rides like the OME medium.
I was planning on removing the helper spring next round, or just biting the bullet and buying a new set of medium springs to see if I can get a better match set.

The Dobinson spring are not marked like the OME springs. (-,o,+).

@locklaw adding different spring rates to the rear seems like it would be bad for driving characteristic?

Thank you for the help gentleman!

 

[locklaw]

Measured from lower lip of rim thru the center of the hub:
View attachment 3264664
View attachment 3264670

I am running 22psi in both rear tires.

I added a leaf to each pack in the rear at the same time I added the 3/8” spacer. Helper spring just make it stiff. Shocking it know! The Dobinson heavy rides like the OME medium.
I was planning on removing the helper spring next round, or just biting the bullet and buying a new set of medium springs to see if I can get a better match set.

The Dobinson spring are not marked like the OME springs. (-,o,+).

@locklaw adding different spring rates to the rear seems like it would be back for driving characteristic?

Thank you for the help gentleman!

Happy to help! Ok, if you have enough leaves nothing stops you then to take one out on the higher side to level it out. One does not want to take a leaf out of a thin pack for fear of breaking a leaf when carrying heavy weight over rough terrain.

We frequently run differing packs/spring rates left and right on new 70 series Cruisers (including my personal ones) which often run 100mph over extended distances (we have, lets say, lackluster law enforcement) or tow stupid heavy loads over horrid roads without adverse effects.

The main aim after you have set up the suspension ride height is to get not only the toe and caster correct but also, to ensure the total runout front to rear is not out of spec. The nature of different asphalt roads' construction will always fight a vehicle with twin solid axles. You can either set it up with the steering wheel straight on the interstate or straight on two lane roads, never both.

 

[-MaTTi-]

Swapping the springs seems like a plausible solution. The rear spring rates don’t seem to be even. I can’t see how the drivers side could be that much heavier, with the tire removed.

I don’t know what’s wrong with these, every 40 starts to lean left.

Mine was quite well leveled when the new springs were installed, but now after 2 year sitting it leans 1” to left (not ready yet, just test drived few hundred yards).

Now it’s lifted/twisted (jack below left front) so that it leans to right quite a lot. Let’s see if it helps after couple months.

 

[OPMACHINE]

Interesting, I had assumed running mismatched spring rates would be bad for handling characteristics. But this is a luxury tractor not a Porsche.

In the front, Im running 3 degree caster shims and 1/8” toe in. She drives straight and stops straight. She just looks goofy with all that lean.

 

[OPMACHINE]

The MUD consensus seems to be that the driveline causes the hot riveted frames to twist.

This is the 3rd suspension i have had under this LC.

- The HFS sat level without issues but was very stiff.
- The OME was corrected with a 3/8” spacer. Improved ride but still stiff.
- The Dobinson leaned 2” to driver without a spacer and 1” with a spacer. Ride was much better before I added the add-a-leaf.

 

[OPMACHINE]

Been a little while sense I checked in:

I finally got the suspension riding level, but it took some cobbling.

Figured out the speedometer drive gear mystery with the drive gear.

 

[wngrog]

Did you try to swap the springs side to side ?

 

[OPMACHINE]

Yes I have tried swapping the spring side to side with no change. Currently I have a heavy spring on the driver and medium springs with a 1/2'' of spacer on the passenger side.

 

[wngrog]

Yes I have tried swapping the spring side to side with no change. Currently I have a heavy spring on the driver and medium springs with a 1/2'' of spacer on the passenger side.

Damn. That’s crazy. I had a 60 with a big tilt once. Not a 40

 

[OPMACHINE]

Hard to imagine its not a frame issue.

I have been thinking about leaving it parked on a ramp overnight or setting the whole cruiser down my big weld table and pulling the frame down with HD strap. I am going to keep tinkering with it.....Hot riveted frame is hardly rigid and I am not going to let it beat me.

It drives great. I pulled that top and doors off last weekend for more smiles per mile.

Next A/C mod:

 

[EWheeler]

Not sure if your attention to detail would allow it, but you could utilize different length shackles to try and correct ride height or get it closer. Wouldn't affect the ride as much as farting around with leaf spring rate. Yes, spring rate is slightly affected by shackle angle, but I suspect it wouldn't be noticeable.

 

[pb4ugo]

Not sure if your attention to detail would allow it, but you could utilize different length shackles to try and correct ride height or get it closer. Wouldn't affect the ride as much as farting around with leaf spring rate. Yes, spring rate is slightly affected by shackle angle, but I suspect it wouldn't be noticeable.

I made a longer shackle in my situation. It's not as noticeable as the lean was. It is currently a trail rig.

 

[EWheeler]

I made a longer shackle in my situation. It's not as noticeable as the lean was. It is currently a trail rig.

You could actually end up with a much much better ride and equal ride height by going longer shackles, ditch the AAL & leveler block/spacer, and relocate the shackle hangers to maintain proper ride height & shackle angle.