A Body Spindles
 

I am pretty sure there is a difference in the height of A Body disc brake spindles between 67-72, some are taller than others even though they are technically interchangeable. Does anyone know which of these years have the tallest spindle. Thank you.

A-body spindle height (64-72) remained the same. But I *think* I see where confusion
might arise? You mentioned 67+. Discs were introduced that year. There's a difference
between the drum and disc spindles, it's the thickness of the boss for the big upper bolt.
But it's on the face, not the overall height. Mill off the appropriate amount from a drum
spindle and you've got a disc spindle. HTH.

They're not "spindles". Spindles are only a part of the steering knuckle, they're the long tapered rod that support the wheel bearings. On some steering knuckles, the spindle is an integral part, on others the spindle is bolted or pressed or welded into the knuckle.

The spindles on my 67 LeMans are quite a bit taller than the spindles on my 65 LeMans both have disc brakes. I need to find a taller spindles for my 65 like the ones on my 67. If they are all the same size then why does my 67 have taller spindles?

If they both aren't the same height, one of them isn't 64-72 A-body. The second gen
F-bodies and various B-bodies used taller ones. Easiest way to tell is the original stuff
used a separate steering arm (pictured below). If it's integral, it's been swapped.



https://i.ibb.co/k6TDxLm/s-l300.jpg

I am currently out of the country on business and won't be back home until October 17th and will take a look at the spindle on my 67. I know the spindle on the 65 the shorter one has a separate steering arm and I am pretty sure the 67 with the taller spindle is the same. I will verify this when I get home.

Be careful with 'new' 'replacement' Steering knuckles/spindles, there are quality issue with them, and have been numerous reports of failures. (Check pro-touring.com if in doubt)

Don't buy drop spindles, those have a higher rate of failure.


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Tim: did someone do the "tall spindle conversion" ?
242177 is correct for ID

'64-72 A-body spindles are all the same height & design. The only difference is '64-66 spindles were machined for smaller diam bolts that attach the steering arms.

Original GM A-body steering arms break down as:
'64-66 (two smaller diam holes for steering arms)
'67-70 (slightly larger diam holes...)
'71-72 ("beefier" castings, easy to spot)

More factory front suspension details...

Original Saginaw outer tierods, inner tie rods, & their respective sleeves, all increased in diameter for '71 model GM A-body's.

Original Saginaw upper ball joints are cosmetically different (tall protusion tops) for '70-72 A-body's. Much different in appearance than their predecessor, the late '60's version. For some odd reason, original '70-72 Grand Prix upper control arms retained the slight domed upper ballpoint that was used on late '60's GM A-body & '69 GP upper control arms. Found that odd last week but confirmed on own '69 as well as nearly a dozen decades parked '70-72 GP partscars.

OPH
I ran across this when rebuilding my 68 drum brake suspension.
Original spindle was scored so I found a good one from a muscle car junkyard. When I went to install it I noticed the backing plate mounting bolt hole was larger in diameter than my original. Contacted the yard who said it came from a Chevelle but they would take it back. Found a correct one later on.
Ever see this before?

Ed, have quite a few 5 gal buckets full of loose spindles, I will have to double check. Most are of the style you have pictured on the top & Ive parted many many more '68-72's, than early cars. Have machined, center bored, & tapped many of the style you have pictured on the top to make disc spindles out of them. Last week, a good Pontiac restorer buddy was here for over a week, & we took time, & went through quite a bit of my parts stock looking for early GTO drums. After that, can say I dont have any '64 or '65 loaded spindles to double check.

You don't need to do that. I found a good one shortly thereafter. I always assumed (incorrectly it seems) that they were all the same. You and Scarecrow made this a learning moment. Thanks.

My 67 LeMans came with drum brakes up front and I bought a disc brake conversion kit from Inline Tube and it works great and the car brakes and handles very vice. I recently bought a disc brake conversion kit for my 65 LeMans from another vendor. I was comparing the spindles between both cars and noticed the spindles on the 67 are quite a bit taller and I would like to get the same spindles for my 65 so I could have more travel. So I am very curious what spindles are on the 67. The kit for the 65 did not include the steering arms so I need to get them separately.

You were NOT comparing "spindles"; you were comparing steering knuckles. The "spindle" is the sticky-out "pe nis" part, that the wheel bearings ride on. The spindle may or may not be an integral part of the knuckle. A cast-iron knuckle is going to have a steel spindle pressed/bolted/welded/swaged in place, a forged-steel knuckle might have the spindle formed from the parent piece of forged steel, machined to shape.

"More travel"? More travel where, or of what?

The "tall" steering knuckle likely has LESS travel side-to-side, which is why the turn radius increases.

Up 'n' down travel is controlled by the bump stops, not the knuckle.

I expect the "tall" knuckle is from a newer A, B, F, X. It might be some aftermarket knockoff, or it could be an aftermarket design owing little to OEM components.

Photos? Casting numbers? Link to the vendor's information on your "Kit"? How could we know what's on your car unless you provide some additional information? We're just guessing, but the "best guess" is that you have some version of the cast-iron GM steering knuckle from the A-B-F-X first used in 1970, and last used on...the '96 Whale "B"-body? They came in early and late versions (later was "computer designed" to reduce weight while maintaining strength) and 11" and 12" rotor diameters, with various bearing sizes.

The spindle is the part that the rotor or brake drum attaches to and I suppose you could call it an axle too, you think I don't already know that?????? It's all one assembly you can call it a knuckle or what ever you want to I don't need you to play Mr. know it all these assemblies are commonly called spindles. I asked that question as to the applicability of the spindles included in their kit to inline tube and their tech guy told me they were factory 1970 spindles. I guess that may not be correct so I have no idea what they are. There are a few reasons why people like taller spindles as it affects how the vehicle corners and handles but in my case the 65 is my drag car and more travel equals better weight transfer on launch and yes it will give me more travel with a taller spindle. I'm currently stuck in Tokyo for a few weeks on business but when I get back home I will take a good look at those spindles on the 67 and take a couple pics and post them and maybe someone can help me figure this out. I appreciate everyone's comments and setting me straight on that that all factory 64-72 spindles are the same.

From a Camaro/Firebird???


OK, the suspension would have some additional travel before the bump-stop hit the upper arm, if the steering knuckle was taller. Now that makes sense to me.

The guy at Inline Tube said the spindles were 1970 A Body.

Close but no cigar if you are only talking about Pontiac A Body spindles and do not split out the disc brake spindle (different upper BOSS height) vs the drum brake spindle boss height. (How far the boss thickness outward is).

Tom V.

If you use the '69-'72 knuckles/spindles from any A body, they will be the same height/dimensions as your old drum brake spindles. I'm talking the set-ups with the single piston calipers, not the old '67-'68 4 piston calipers. Have done this swap using '72 knuckles on a '65 GTO and the measurements were exactly the same.

10 years ago the Tall B-body spindle was a DIY way to upgrade to the 1LE rotors / calipers.

I didn't there were tall OEM A-body spindles.

I'm not comparing drum brake spindles with anything. I don't have any drum brake spindles on my cars unless the disc brake kit I got for the 65 came with drum spindles. I am comparing the disc brake spindles on my 67 LeMans with disc brake spindles on my 65 LeMans. OK do they make a disc brake kit that uses the drum brake spindle? If so then maybe this is the issue maybe the kit I got for the 67 was based on a disc brake spindle and the kit I bought for the 65 was based on a drum brake spindle?

Is there a difference in height between a drum brake spindle and a disc brake spindle for an GM A-Body?

No, they are all the same.


Sent from my iPhone using Tapatalk Pro

If you did a disc brake swap that included new spindles (knuckles), it's likely they used a spindle (knuckle) that is not 'native' to your car. It's that simple.

There are a multitude of spindles (knuckles) that are compatible for the tall spindle (knuckle) swap, as mentioned on the GW website:

"Donor cars with tall spindles and 11 inch disc brake rotors:

Buick full size 77-81, Century 73-77, Riviera 77-78, Skylark 75-79, Cadillac Seville 76, Chevy full size 77-81, Camaro 70-81, Chevelle 73-77, Monte Carlo, Nova 75-79, GMC Sprint 73-77, Pontiac full size 77-81, Firebird 70-81, Grand Prix 73-77, Lemans 73-77, Phoenix 77-79, Ventura 75-77, Oldsmobile Cutlass 73-77, Omega 75-79

Donor cars with tall spindles and 12 inch disc brake rotors:

Buick full size: LeSabre wagon/Electra wagon 77-94,Cadillac Fleetwood/Deville 77-84, Brougham/Fleetwood 85-94, Chevy full size: Bel Air/Biscayne/Caprice/Impala 77-96, Olds 98/Delta88/Delta 88 wagon 77-92, Pontiac full size: Bonneville/Catalina/Grandville 77-86

Important: There are two different types of 12 inch disc brakes spindles. One version uses a small outer bearing measuring .750. The second type uses a larger outer bearing measuring .850. Use the larger diameter outer bearing spindle because the rotor you are going to need is off a 1988-92 1LE Camaro/Firebird GM part #18016035. These rotors have the correct bolt pattern 5 on 4 3/4 bolt circle, however the rotors use 12mm studs rather than 7/16 studs. You need to change the studs over to 7/16. We use a DBS-42 kit for this conversion. "

With that said, if it aligns correctly, there should be no concern about any diff in height. If you now switch to a shorter spindle (knuckle), you will also need to change your upper control arms in order to get it to align right, unless you have a massive stack of shims on there now.

If you change to a taller spindle (knuckle) from a shorter one, you need the 'matching' upper control arms. (just to say it out loud).


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OR just use the 12" rotor that came with the knuckle and re-drill it for 4-3/4" bolt circle.

Big car rotors are 'thicker' than the 1LE rotors, so you'll need the corresponding calipers.
(just something to be aware of for anyone that's putting a shopping list together)

Speedway has the 12" rotors with 7/16 studs already in them.

Downside almost all 11 and 12" F/B body rotors are now Chinese. Some used to be Canadian not so anymore.

My 78 Firebird manusal says 78 was first to use the bigger bearings some sources say '79. Never replaced mine so not sure.

I took the info directly from GW...and have not verified, it's been a while since I did tall spindles.

I just go straight to the AFX spindles these days, avoid all the drawbacks, IMO the extra bux are worth it.


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I use regular A-Body calipers on my 12" Rotor Global West suspension.
I DID have to remove the metric studs in the rotor and install the
proper wheel rim studs in the rotors.
Normal A-Body rotors used the typical A2 & A6 bearings.
I had to use the outer A34 bearing for my 12" 1LE rotors.

The majority of the mods just took some time to acquire the parts, but have been installed for many years now.

Tom V.

I think the A34 is a hybrid bearing allowing swapping rotors to the different spindle.

Could be. I really do not care either way as long as it functions properly in the parts I HAVE, and it appears that it is working just fine in MY application.

Be Safe Skip.

Tom V.

So which rotors were the .810" ones?


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Yeah, there's the 'typical' one, which I believe is the .810, and the thicker one, which I believe is 1.05 or so?

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Knuckles for 11" rotors have a big #1 cast on it. Knuckles for 12" rotors have a big # 2 cast on it. I will now let scarebird fill us in with the exceptions !

Got home from Japan finally getting around to posting these pictures. Here are pictures of the spindles the ones with a little rust are on my 67 LeMans and these are the taller ones. These came as a kit from Inline Tube. The second pictures with new and shiny are on my65 LeMans. These are the shorter ones these came in a kit from Pirate Jacks.

Not what I was expecting to see.

I had to look at the ball joints to tell the difference in the photos. Steering knuckles "look" the same to me. Forged steel with forged, bolt-on steering arms; seems like stock knuckles for the single-piston-caliper disc-brake version of the '69--'72 "A" body. They're clearly NOT the cast-iron A-F-X-B-C knuckle.

HOW are you measuring them to know one is taller than the other? Put the tape measure in your next set of photos. Are you sure the "difference in the height" isn't the way the upper ball joint is bolted to the underside of one control arm, but the top side of the other control arm?

I know this is an old thread, but can somebody please confirm whether or not 64-72 DRUM brake knuckles are the same left to right? Or are they side specific? Thanks to anyone that can help.

Johnny

Pretty sure the same just different bolt on steering arms.