Suspension Lurn me on rack mounting bushings

limp

wrap a little cheese around it and its a done
Oct 4, 2020
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So, It seems that urethane rack bushings seem like a good upgrade, while solids might be a bit much for the " grocery getter"?
Some questions
#1. Any brand recommendations?
#2. I am installing an 03 ZK rack I had Turn One go through into my 83.. Yes, it has the correct tie rod ends ... I had new stainless lines installed, Bentley said it was OK..... Yes I took these pics on top of my oven........
#3.. there are 6 bushings in the 79-84 kits, while 85-93 have 4 bushings?? Can anyone tell my why the difference?
#4. I see some offset bushings offered? When would these be used...
As always all help appreciated....
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I've only had experience with prothane ,they have been great for a few years now, don't remember where the hell I got them.
 
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The rack was completely different for 79-84, so the bushings were different. Since you are doing the ZK rack you’ll want the newer ones.


Which K-member are you installing this on? That will kinda tailor the answer a tad.

I ran the Prothane urethane rack bushings. No complaints and was not harsh at all. I now have the MM solid offset bushings.

The stock 83 K member with SN95 spindles and upgraded brakes....
 
SN95 generally refers to 94-98 with New Edge referring to 99-04 (though actually I believe the entire 94-04 is on the SN95 platform).

Anyway, back on topic...

The answer to whether to use offset or centered rack bushings is a function of how are you planning to sort out the bump steer question.

You want a line drawn through the lower control arm bushing and ball joint pivot and a line drawn through the inner and out tie rod pivots to be parallel (ideal situation). If not you will have some level of bump steer.

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As seen here, mine are almost parallel. If you look at the rack bushing, I offset my rack down. If I had offset mine up (like most people with 94/95 spindles do) my angle would be much worse. I have '00 spindles with fox length control arms and relocated the control arm mounts up approx. 1/2" and inward 1/2" (so mine are now as far in as yours). I have no bump steer kit and use stock fox tie rods - actually a bump steer kit would make mine worse.

My setup is not perfect, but its close enough for me. Perfect would be control arm length (bushing center to ball joint pivot center) and tie rod pivot length (distance from inner pivot to outer pivot) equal and the two lines perfectly parallel. My control arm is about 1/2" shorter and you can see how close to parallel the two lines are.

So based on your spindles and moving the lines above for that tie rod connection point, I would probably go with offset bushings set up to move rack up.
 
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Thanks for the pic and answers...
So are you saying that the stock mustangs have a bump steer problem from the factory?
Or am I changing the geometry using the 94 spindles?
I was under the impression that the 94/95 spindles are preferred ( to upgrade to 5 lug) as they keep the angles the same, unlike 96 up do?
Just picking your brain here..... Thanks
 
Thanks for the pic and answers...
So are you saying that the stock mustangs have a bump steer problem from the factory?
Or am I changing the geometry using the 94 spindles?
I was under the impression that the 94/95 spindles are preferred ( to upgrade to 5 lug) as they keep the angles the same, unlike 96 up do?
Just picking your brain here..... Thanks

No, in stock form, ford did a decent job with bump steer. It's when you lower the car that it becomes an issue.

Since you are keeping the stock K-member,, the rack remains in the stock location. 94-95 spindles are preferred here.

As to if you need offset bushings, it depends on how much you plan to lower the car. The thing with bumpsteer is that it really should be measured. I know you can somewhat eyeball things, but in measuring my bumpsteer after eyeballing, i was still way off. I'm not saying you need to measure it, but don't expect it to be perfect without doing so.

For the sake of simplicity, i would just do the standard poly bushings. My car was lowered and I ran then as is for a couple years like that.

The offset bushings I would lump into a bigger discussion over suspension plans and such.


One thing to note. With the 1983 K-member, you might need to convert to the 1985 steering rack mounting sleeves and bolts. You can find these used on ebay, but i'm just linking here so you know what I am talking about.


 
One thing to note. With the 1983 K-member, you might need to convert to the 1985 steering rack mounting sleeves and bolts. You can find these used on ebay, but i'm just linking here so you know what I am talking about.


I have not taken the 83 front end apart ( its in a holding pattern till I sell a car or two) so my only experience has been with 94/95 and 03/04 cars at the wrecking yard taking spindles and steering racks.......
Do the 84 and older cars have a bolt only without the sleeve, that attaches the rack to the crossmember?
 
@KRUISR you typed, (and has bugged me since) -
“SN95 generally refers to 94-98 with New Edge referring to 99-04 (though actually I believe the entire 94-04 is on the SN95 platform).”
The SN95 is the platform. New Edge is the styling. The switch to the mod motor and some other changes or upgrades did not change those basics. It’s enthusiasts that are looking for different ways to specify which car without specifying the year.

@limp what is the issue or not with the differences, and can you be more specific?
 
LOL.. forgive me, I took out the rack on my 83, Took some pictures and never added them to my post....
Was going to show the size difference of the rack mounting bolts from the 84 and older cars.....
Figured you lifers have all seen it before............
Had thought of using the older style urethane bushings in my new 03 rack, but I believe the OD of the bushings is different.. MUCH heavier duty looking
Too hot ( Florida summer has come) to fight them today, but getting the bushings out of my 83 rack seem to need a press.....
 
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I have used both urethane and the solid aluminum rack bushings in different cars and I honestly never noticed a difference between the two types. The last two mustangs I lowered I used the urethane offset ones because they are cheaper.
 
LOL.. forgive me, I took out the rack on my 83, Took some pictures and never added them to my post....
Was going to show the size difference of the rack mounting bolts from the 84 and older cars.....
Figured you lifers have all seen it before............

I’d figure a good chunk of us here are 87+ folks and pre-87 is one giant mystery. So let’s see it.


I mentioned once a long time ago that early 2.3s (79-83) had a 6.75” axle in them and heads just exploded
 
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Ok, due to popular demand.........
Again these pictures are what came out with my steering rack from my 83, 5 liter, GLX vert..
I see the new replacement ( Catalog) bushings ( 79-84) call for 6 of them.. Not sure about that, as I see 4
Based on my service manual, the pic side bushing goes the entire length surrounding the sleeve.. The other side seems to be a smaller bushing
The holes, in the K member, where these attachment bolts run through look too large for the " built in washer" on the smaller/newer bolts to work.. Planning on a large washer at this point, but I will look things over after I get the K member out...
The sleeve the bolts run through are pretty darn heavy duty looking...
As I said before, looks like the bushings are almost pressed in...My Ford service manual does not have any detailed removal instructions for the bushings/Sleeves....
The smaller diameter bolts are what came out with the rack I purchased from an 03...
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