New rims and tires and uncontrollable

[Cornfed]

Today I bought 17" rims and 285 70 17 tires - from Hankook...

I came so close to flipping my rig driving home - it scared the life outa me.

I was running Super Swamper 35's x 12.5 on 15" rims -

The truck is lifted and everything is done right - Rancho 9000 all around - I adjusted them to try and even out the ride - I can not go over 35mph!

I am a newbie to Jeep - but built FJ40's before this -

The truck is a 69 CJ5 -

 

[Tinman22]

What did it do? Shake,shimmy,vibrate,wobble,pull, maybe with its new tires it just wanted to go where it was built to go ..off road! No really what did it do?

 

[73CJ]

You still look pretty high. Do you know how high your lift is?

Are you running sway bars? Probably needed.

Tires balanced etc? Alined?

More photos might help us figure this out.

 

[csuengr]

I have 35 x 12.50 15's on my CJ and they are very sensitive to air pressure. If I run them at 35 psi, it's uncontrollable. I run them at 10-20 psi and it is much better. The tires wear better also. I am probably a little shy on caster, but not worth messing with at the moment.

 

[Cornfed]

I have 35 x 12.50 15's on my CJ and they are very sensitive to air pressure. If I run them at 35 psi, it's uncontrollable. I run them at 10-20 psi and it is much better. The tires wear better also. I am probably a little shy on caster, but not worth messing with at the moment.

It does not shimmy, shake or wobble - the alignment is good -

The problem was - I got on the road and got up to speed and you barely touch the steering wheel and it jumps to the next lane -

I would say probably six inches of lift - the sway bars seem solid -

Lower PSI ? onroad ?

and yep, I agree...offroad!

I will go take pictures - hold on -

oh and thanks - the old tires and rims are going on on the morning....

 

[Old Dog]

- the old tires and rims are going on on the morning....

So your saying it drove fine with the old tires?

 

[Cornfed]

So your saying it drove fine with the old tires?

It was not perfect but it went 70mph down the road - but the Super Swampers were worn..I drove 340 miles to the trailhead this weekend...

 

[csuengr]

Tire pressure is something that can be tuned. We had a tractor and the rear tires were rated at 8000 lbs load at 12 psi. Pressure is sort of a function of volume. I run at 18-20 psi and the handling is much better and the tires wear almost even. I have too much positive camber on the front axle to get even wear.

 

[Tinman22]

How was the tread wear on the front ssr's. Were they worn more on the outside or inside or even across the whole tread ? Even a few 32nds could cover up a problem . Improper toe caused the same twitchyness your describing. Mine was a bent tierod .

 

[Cornfed]

How was the tread wear on the front ssr's. Were they worn more on the outside or inside or even across the whole tread ? Even a few 32nds could cover up a problem . Improper toe caused the same twitchyness your describing. Mine was a bent tierod .

I will check that in the morning - it seems to track straight -

The SSR seemed to have even tread wear across -

Tomorrow - before I switch em back out - I am going to decrease the PSI and increase the PSI - I had a guy call tonight and say "well they are only at 35...so ?

Confused...but that is what is fun about Jeeps -

 

[Tinman22]

I ran 37" ssr's on my 7 for 3 years and loved them I switched over to baja ta's the same size and had the same problem. Put the ssr's back on it went away. Drove me nuts for weeks. Tread looked even but it wasn't . A bent tierod (read hit a stump) that you could barely see had toed my front end in. Wife still won't ride in it! Not all bad I guess!

 

[tarry99]

It does not shimmy, shake or wobble - the alignment is good -

The problem was - I got on the road and got up to speed and you barely touch the steering wheel and it jumps to the next lane -

I would say probably six inches of lift - the sway bars seem solid -

Lower PSI ? onroad ?

and yep, I agree...offroad!

I will go take pictures - hold on -

oh and thanks - the old tires and rims are going on on the morning....

Cornfed

Thats a nice looking early CJ......what is on the 225 manifold ...Carb or Injected?

Looks like someone did a spring over suspension and used a longer & wider Wrangler type spring & extended shocks...............Looking at the front end and it's hard to judge from the picture but it looks like the front may be a little short on Caster Angle on the front axle. Might want to check that.

Also a good sway bar for driving that on the Highway may make a lot of since also............A wide track CJ bar should go under that. Looks like your frame width is still stock put your spring perches have been moved out so you would need to measure it...............Just a thought

 

[Cornfed]

I ran 37" ssr's on my 7 for 3 years and loved them I switched over to baja ta's the same size and had the same problem. Put the ssr's back on it went away. Drove me nuts for weeks. Tread looked even but it wasn't . A bent tierod (read hit a stump) that you could barely see had toed my front end in. Wife still won't ride in it! Not all bad I guess!

Yep, I am going back to the 35's today - I hear ya on the wife!! lucky!

Cornfed

Thats a nice looking early CJ......what is on the 225 manifold ...Carb or Injected?

Looks like someone did a spring over suspension and used a longer & wider Wrangler type spring & extended shocks...............Looking at the front end and it's hard to judge from the picture but it looks like the front may be a little short on Caster Angle on the front axle. Might want to check that.

Also a good sway bar for driving that on the Highway may make a lot of since also............A wide track CJ bar should go under that. Looks like your frame width is still stock put your spring perches have been moved out so you would need to measure it...............Just a thought

Yep, I bought it lifted - the guy did not know what the ARB things were "but it has this cool compressor"...and he gave me two long bars that came with the truck - which I am trying to figure out. and the split case he thought was only 4wd for lw, super low, super super low...I just smiled.
Thanks for looking underneath...when it comes to Jeep suspension I am clueless...

Oh, and it still has the carb - it was rebuilt at 99,999 and the odometer runs backward - so about 10k on the rebuild - runs really nice!

 

[jasonmark1993]

Id agree with a caster issue and you just didnt notice it with the big heavy swampers on there.

 

[Cornfed]

Id agree with a caster issue and you just didnt notice it with the big heavy swampers on there.

I went back to the big heavy Super Swamps - little drift but not as noticeable - I thought of taking the power steering belt off and trying Ole Iron with it - the steering is so touchy with PS...

I agree on caster - now how to correct?

 

[jasonmark1993]

Anything that rotates your axle will change the caster. So unless you chop the knuckles off and reweld, you'll be moving the pinion angle also.

I went to a longer shackle on the front of my CJ5 and noticed the steering got a little lighter.

Looks like you have a ton of room up front. I didnt see how long the shackles were but you could try some shorter ones.

 

[Kane]

That looks like a scout axle which has zero caster from the factory. I bet the guy who did the SOA just kept it all the same. If the super swampers were bias ply then you would not have an issue because they create there own caster from flex carcass which is how the scouts were set up. The new tires are radials an since you have bigger rims with less side wall that adds to the stiffness of them and makes that even worse.

 

[Cornfed]

That looks like a scout axle which has zero caster from the factory. I bet the guy who did the SOA just kept it all the same. If the super swampers were bias ply then you would not have an issue because they create there own caster from flex carcass which is how the scouts were set up. The new tires are radials an since you have bigger rims with less side wall that adds to the stiffness of them and makes that even worse.

That makes sense - I have been wondering where the axle's came from and what they are - the fun of the Jeep is whoever set it up never wheeled it - the undersides are clean and so I am trying to tweak it and make it drive able as a daily driver for hunting and around the ranch -

 

[micrablue]

Cornfed,

You're scaring me. I also just bought new 17" (beadlocks) and new Toyo AT 285/75R17LT's and RS9000's. Go figure.

But I have a CJ7 and no SOA; I am running 4" Skyjacker, reverse shackle system, with 1" shackles, and sway bar. I just sold off my Toyo MT 35's, which I routinely turned at 70-75mph, smoothly.

For my new wheels and tires, I am going to run dynabeads inside to ensure they balance. The rest I am entrusting will be status quo as before.

For you, I would recommend ensuring all your current parts are not worn out, especially ball joints and bearings. Then check your leaf springs for wear, to include bushings. Although adding a swaybar helps with roll, it adds stability. Then check into adding a trackbar for the front. I am building one for mine, but only because I want to steer with a finger as I drive, which it's pretty close to steering like that now.

I am just getting too old to put up with a wandering Jeep like I did back in high school days. That was wanna-be suicide. Don't need anymore premature white hairs!

 

[Cornfed]

Cornfed,

You're scaring me. I also just bought new 17" (beadlocks) and new Toyo AT 285/75R17LT's and RS9000's. Go figure.

But I have a CJ7 and no SOA; I am running 4" Skyjacker, reverse shackle system, with 1" shackles, and sway bar. I just sold off my Toyo MT 35's, which I routinely turned at 70-75mph, smoothly.

For my new wheels and tires, I am going to run dynabeads inside to ensure they balance. The rest I am entrusting will be status quo as before.

For you, I would recommend ensuring all your current parts are not worn out, especially ball joints and bearings. Then check your leaf springs for wear, to include bushings. Although adding a swaybar helps with roll, it adds stability. Then check into adding a trackbar for the front. I am building one for mine, but only because I want to steer with a finger as I drive, which it's pretty close to steering like that now.

I am just getting too old to put up with a wandering Jeep like I did back in high school days. That was wanna-be suicide. Don't need anymore premature white hairs!

Make sure you let me know how it rides (not wanders) I have plenty of grey hairs from getting hit by a semi in South Korea when I was much younger - I too do not need anymore - I also would like to see your trackbar build for the front - I think that might be a wise way to go / everything front and rear are new - but - (and a big but) it has 10K on the rebuilt motor, tranny, and SOA - which tells me that in 15 years since the build - no one has felt safe drivin Ole Iron. So I am trying to figure out how to either incorporate a sway bar - run the Rancho 9000's on firm - or...she just has tooo much springyness in the front end.