Suspension Redo (1 Viewer)

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I have a fairly new to me 1976 FJ40. Previous owner did an engine swap for a chevy 350, chevy 300 auto trans. They also added a 2 inch body lift and a 4 inch rough country lift. The steering box has been changed to a GM camaro box. It doesn't look bad but it doesn't drive well. It wanders all over the road even at 20 mph. I'd expect some but its a lot. I'd like to make it a daily driver and I'm not sure where to start with trying to make it more driveable. I did have a shop look at it and says all the joints seem tight, he suggested sway bars and spacers to push the wheels out. I'm thinking of checking out an Old Man Emu lift and removing the body and rough country lift. Thoughts?
 

pb4ugo

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Your 4" suspension probably has probably altered your caster angle on the frt end. Your desciption of your steering issues are classic signs of negative caster. The frt end needs positive caster to help with tracking and steering return. Also check the condition of spring bushings and make sure the ubolts ate tight. You need to find out what the current caster angle is, then make the proper adjustments with caster shims.
 
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Your 4" suspension probably has probably altered your caster angle on the frt end. Your desciption of your steering issues are classic signs of negative caster. The frt end needs positive caster to help with tracking and steering return. Also check the condition of spring bushings and make sure the ubolts ate tight. You need to find out what the current caster angle is, then make the proper adjustments with caster shims.
that sounds good. I'll check that out and report back. Also, I should have mentioned, the steering box now sits right behind the bumper, my research shows that is not standard.
Thanks
 

pb4ugo

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Do you have saginaw power steering? That's most likely a normal conversion. Pics would help. Negative caster gives a feeling of white knuclke driving and little steering inputs make it feel like your chasing it to correct direction.
 
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Do you have saginaw power steering? That's most likely a normal conversion. Pics would help. Negative caster gives a feeling of white knuclke driving and little steering inputs make it feel like your chasing it to correct it.
very well could. Its a saginaw box. I will get some pictures a lunch thanks
 
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here's some pictures. As you can see the steering box is between the bumper and the grille.
IMG_20210405_110040777.jpg
IMG_20210405_110105074.jpg
IMG_20210405_110049499.jpg
 

77mustard40

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Your 4" suspension probably has probably altered your caster angle on the frt end. Your desciption of your steering issues are classic signs of negative caster. The frt end needs positive caster to help with tracking and steering return. Also check the condition of spring bushings and make sure the ubolts ate tight. You need to find out what the current caster angle is, then make the proper adjustments with caster shims.
Doesn't look like there are shims under the front axle, so caster most likely needs to be addressed to help with the wandering. I'd check tie rod ends and toe in setting as well.
 
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You have a lot to consider. Caster would be the first thing I would look at as it could correct the steering issue. Removing the lifts is another can of worms. You can't remove the body lift without having to redo the power steering box mount and its' connection to the steering shaft. If you replace the spring lift that could affect the castor negating any prior castor correction. Not to mention possible tire clearance issues.
 
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You have a lot to consider. Caster would be the first thing I would look at as it could correct the steering issue. Removing the lifts is another can of worms. You can't remove the body lift without having to redo the power steering box mount and its' connection to the steering shaft. If you replace the spring lift that could affect the castor negating any prior castor correction. Not to mention possible tire clearance issues.
I like the lift just willing to do what I need to do to.get this thing out on the road safely. Will start with caster and see where it goes.
 

pb4ugo

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Ive never seen a sag box adapted that way. We probably need a pic from the frt so we can see the tre's from end to end along with drag link from the box to the tre. With that box above the frame, the drag link could be at a pretty steep angle, which would cause bump steer.
 
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Ive never seen a sag box adapted that way. We probably need a pic from the frt so we can see the tre's from end to end along with drag link from the box to the tre. With that box above the frame, the drag link could be at a pretty steep angle, which would cause bump steer.
You guys are great! I'll get se.more.pictures tonight.
 
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Ive never seen a sag box adapted that way. We probably need a pic from the frt so we can see the tre's from end to end along with drag link from the box to the tre. With that box above the frame, the drag link could be at a pretty steep angle, which would cause bump steer.

The box was mounted above the front crossmember to avoid cutting a hole in it. You normally wouldn't be able to do it with the body lift. Could possibly be done but would require surgery to the front sheet metal.
 

pb4ugo

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The box was mounted above the front crossmember to avoid cutting a hole in it. You normally wouldn't be able to do it with the body lift. Could possibly be done but would require surgery to the front sheet metal.
I see what they did. The box is approx 4" higher than normal for sag conversions. This increases the drag link angle to the tie rod. Even with a drop pitman arm the angle would still be pretty steep. If the drag link is too steep it will apply downward pressure on the tie rod and create bump steer too. I'm curious to see what these links look like.
 
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I see what they did. The box is approx 4" higher than normal for sag conversions. This increases the drag link angle to the tie rod. Even with a drop pitman arm the angle would still be pretty steep. If the drag link is too steep it will apply downward pressure on the tie rod and create bump steer too. I'm curious to see what these links look like.
Ok, this should be what you are looking for

IMG_20210405_145709224.jpg


IMG_20210405_145659894.jpg


IMG_20210405_145649050.jpg
 

pb4ugo

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That angle is better than I thought it would be. They did do some major hack to the frame rail and cross member to get the box installed. It looks like the frt bumper was made to help out the weakened frame rail. Have some one turn the wheel back and forth and see if the box moves around and check the caster angle too.
 

Toyoland66

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Yeah that’s got a lot of wonky going on. The hacking of the frame rail like @pb4ugo said combined with the mounting above the framerail plus the extra dropped pitman arm placing a lot of torque on the framerail, I would expect quite a bit of flex under load.

That’s a 3 bolt Saginaw box, most swaps use a 4 bolt.

IMO it should all be redone with the correct 4 bolt box and mounted properly. I would look at the 4x4labs mounting kit as it would replace or reinforce most of what they jacked up. I would replace the pitman with a flatter one to suit the new location. I would also confirm that they used the correct TRE and taper at the pitman arm end of the drag link.

I would also lose the body lift. I can’t see how that would be necessary with the size tire you have. Is it there for drivetrain clearance?

You also need to get some steel caster shims to correct for the longer than stock shackles.
 
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Yeah that’s got a lot of wonky going on. The hacking of the frame rail like @pb4ugo said combined with the mounting above the framerail plus the extra dropped pitman arm placing a lot of torque on the framerail, I would expect quite a bit of flex under load.

That’s a 3 bolt Saginaw box, most swaps use a 4 bolt.

IMO it should all be redone with the correct 4 bolt box and mounted properly. I would look at the 4x4labs mounting kit as it would replace or reinforce most of what they jacked up. I would replace the pitman with a flatter one to suit the new location. I would also confirm that they used the correct TRE and taper at the pitman arm end of the drag link.

I would also lose the body lift. I can’t see how that would be necessary with the size tire you have. Is it there for drivetrain clearance?

You also need to get some steel caster shims to correct for the longer than stock shackles.
Thanks for the info. I was kind of at the point to just take it all off and start again. Want it reliable and safe.

The lift and body lift were done by po who had 39 inch swampers on it and only used off road. It's going to be my beach cruiser and hopefully our tow behind if we can get issues worked out.
 

pb4ugo

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Yeah that’s got a lot of wonky going on. The hacking of the frame rail like @pb4ugo said combined with the mounting above the framerail plus the extra dropped pitman arm placing a lot of torque on the framerail, I would expect quite a bit of flex under load.

That’s a 3 bolt Saginaw box, most swaps use a 4 bolt.

IMO it should all be redone with the correct 4 bolt box and mounted properly. I would look at the 4x4labs mounting kit as it would replace or reinforce most of what they jacked up. I would replace the pitman with a flatter one to suit the new location. I would also confirm that they used the correct TRE and taper at the pitman arm end of the drag link.

I would also lose the body lift. I can’t see how that would be necessary with the size tire you have. Is it there for drivetrain clearance?

You also need to get some steel caster shims to correct for the longer than stock shackles.
I agree with most of toyotaland66 says. I would make the corrections. Then, I would probably look at using the drop pitman arm and use the proper gm tre. You would need a custom drag link. Having the drag link closer to parallel to the tierod is usually better. Looking at your pics, ot looks like you have a stk fj40 tre attached to the pitman arm. That arm most likely has a larger tapered hole than the taper of a stk fj40 tre. In the past some folks have installed a bushing to take up the difference between the 2. It could be a sloppy fit and contributing to your steering slop. There are vendors on here that also offer drag links and tre's to cure this connection.
 

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