Serious steering issue - 79 Scout II - detailed info

[JerryD]

Originally Posted by Tom

Can someone possibly provide IH factory alignment specs?

This is what I have from CTS-2565P which covers my '76.

Camber (built-in) --------------- 1*, +/-.5*
Caster (built-in) ---------------- 0*, +/- 1*
Knuckle Pin Inclination ---------- 8.5*
Toe-in ------------------------- 1/16" +/- 1/16"

HTH,
Jerry

[Brian-Ks]

stock alignment specs for the three that are gonna be done at most alignment shops are:

caster = 0*
camber = 1* plus or minus 1/2*
toe in = 3/32" - 5/16"

* = degree

those castor correctors shouldn't of put you in the negative. i think the max correction on those is up to 1.5* positive caster. those can also be used for camber as well.

over-inflation will result in center tread wear.

wear from improper toe settings will actually give you a "feathering" across the tread, alot of the times in a diagonal line.

wear on the outside edge of the tires in the front is from too much positive camber. tires look like \ / though not that intense.

you mentioned the rear end having one tire further foward than the other, which is setback. not sure if there was supposed to be any but since scouts are rear wheel drive it could affect your thrust angle. this probably wouldnt contribute to the severe bump steer you describe. but i'd crawl under and make sure no ubolts were loose, no broken spring centering pin, etc.

i'd take it to another alignment shop if i were you. besides, most shops that do alignments just give the old "toe and go" anyways.

try swapping tires like a few have mentioned. also check the condition of your rag joint. if there's enough flex in it from too much steering fluid and other grime on it then it doesnt take much of a bump to rotate that steering shaft especially towards the steering box input shaft to make it jump around.

you said it tracks nice and straight though right?

no pull in either direction under normal driving?

the vehicle will pull to the side with the LEAST caster (pos. or neg)

the vehicle will pull to the side with MOST camber (positive or negative)

but a slight variation in each can cancel each other out and you wont notice any pull at all.

for the most part, you dont want more than .5 degree of variation between either side (caster or camber)


but first, i'd address the steering flex on the frame, maybe take the box off and clean it up and check, then while you have it off reinforce the area with a minimum of 3/16" plate to beef it up. you can get alot more problems than you think from flex movement at the steering box, and slop in the box itself. it doesnt take much movement at higher speeds to show severe reactions like you described.

hope that wasnt too much info. and though some of it might not have helped, i hope some did.

[Tom]

Brian in Kansas – your post wasn’t confusing at all… I like hashing out problems here on this forum – Thanks for the specs – same to you too Jerry – thanks for posting them also.

I agree that the caster correctors shouldn’t have put me in the negative. I believe in the product itself, which I guess leaves two alternatives to why the caster was negative – either 1. the axle knuckle has a problem from the factory, or 2. the alignment was improperly done. – I know for a fact I had negative caster. I was standing in the alignment bay reading the results (before we aligned it). Right now I'm sitting here reading the actual results from the alignment we just did.

The feathering you talk of is the tire wear problem I had/have. I called it “scuffing” from heel to toe on the center treads, but as I think of it it could resemble the “diagram” you have drawn. They told me to increase tire pressure and rotate more often. I was rotating every 6,000. They told me every 3,000 and claimed the wear was partly due to the "open void" design of the tire.

I have no wear to speak of on the outside of the tires, which is surprising, as I remember my Dad's Scout II always cupped the tires.

I have a spec on my rear thrust angle. It is -.05* He told me that wasn't bad, and relates he's seen much worse, particularily on new Dodge trucks.

Goes straight as an arrow down the road, if all roads were straight I would have no problems.

Never pulls, but does get a bit unruly in heavy winds (I’m assuming most Scout’s do).

Had to read about the caster/camber/pulling deal twice to absorb it. I have specs on my Scout in that respect also… Cross camber is .6* Cross caster is -.2*

I’m ordering the brace tomorrow. From there I’ll pull the box, replace the leaky seal, clean up the area and checks the welds.

Of course, I’ll report the results.

Thanks for all the info. I love the BB.

Tom

[Arkansas Dave]

I have the same problem with my 79 I run 33x12.50s with new 4 inch lift springs new bushings, new steering box. It changes lanes often especially on uneven pavement. But I did find one thing the other day that I think is going to help some of this my rear eyes of my front springs were moving side to side the new rear bushings didn't fill up the area and it has space on both sides and was shifting back and forth. my tires wear exactly the same way as described.

AD

[Blackdog]

I still have some handling issues on my 72 Scout. It has always been "road wild". No lift, 31X10.5 Michlin's, 2 degree caster shims. Its just OK up to 60 or 70. I put a straight steer on it with no results. I met this guy that owns a frame/alignment shop in Yakima. He's 75 years old and has been a off roader all his life. We have agreed that the lack of caster is the problem. He wants me to go 8 degrees. I put 7 degrees in my SOA Scout and it handles like a dream. I'll put 7 or 8 degrees in the 72 before I leave for the AZIHR. It appears to be the only fix. I've had 8 Scouts including a 1980 that had 2 degrees from the factory, I never had the nerve to take any of them faster than 70 or so. Keep us posted, I'd like to know what your final fix is.

[Tom]

Guys,

Once I get off work today I want to get the Scout home and get it up on jackstands and see what I can do. I will check those spring bushings at the hangars also.

I'll let you know what I find out overall.

TOM

[mark stabolito]

Im gonna suggest you take a look at the rear axle, Make sure your spring center pins are intact and the u bolts tight. Check the fronts as well.

[jeromekirkland]

I agree with mark and as brian-ks mentioned check those rear u-bolts. I had a similar problem and changing the bushings helped a little but then I noticed a little wear on the rear spring spacer where a loose u-bolt was rubbing. the bolt was rusted enough that a casual check with a wrench seemed tight but the wear markes said diff. replaced u-bolt no more sudden shift in lane. still wanders a little but have not done alignment yet.

[Tom]

Gentlemen,

I ordered the steering brace from Rick at SSS yesterday. I hope to have it one within the next two weeks. I'll post an updated thread at that time.

I'm wondering if the frame flex was causing issues with the alignment specs -- they turn the wheels with the engine off to measure caster/camber/toe - when I turned the wheels with the engine off I could watch the frame flex --

Should be interesting to find out the results...

Thanks again for your help and interest in my old SCOUT.

TOM

[mark stabolito]

When you put a car on an alignment rack the frt tires are parked on turn stiles to eliminate most friction when turning the wheels wich minimizes flex. Also i put the straight steer in the "nice to have" category, ( i made my own) dont think not having one should result in scary handling if everthing else is in order. Just this guys opinion, hope you figure it out.