Steering Supports and Knuckles

[woodie49]

This started out as a simple project - just replace my kingpins and get back on the road. No such luck.?

 

Attached are a few pictures of my steering knuckles and supports.  They look like they are the stock correct parts for my '49 Plymouth judging from forum pictures (I have nothing to physically compare) but if you can tell that they are not, let me know. The problem is that the hole in the support is .9745 ID and the replacement king pin is .9765 OD. Since I wasn't sure when or where I bought the pin set, I got a second set from AB and they are identical. So, I can not pound a .9765 pin into a .9745 hole. Even I get that. 

 

My assumption is that my steering supports and knuckles must have come from a different Chrysler product that has slightly different specs.  I assume if I can determine what this came from I could just order the right King Pin set and move forward.?

 

I can not find anything online that provides the diameter measurements of king pins. For a while (not any longer) Rock Auto used one manufacturer that did provide that spec, but all the Plymouths I could find listed the diameter at .796. 

 

My old pin, which really is not re-useable due to wear, is .7945.

 

Can any of you send me to a reference where I might be able to compare king pin diameters? or, better yet, order a kit based on these specs? Or, help me to identify what else these knuckles and supports might have come from?

 

My other option is to have the supports honed out a couple thousandths, which doesn't seem like a lot of material, so I doubt I would give up much strength. But then I wonder if I would need to similarly have the knuckles honed, or if they would already accomodate bushings that would be a couple thousandths too large, since they are a press fit and the bushings have a crush gap built in? Then would reaming them a couple thousandths more to make then thinner to accomodate the bigger diameter pin also prevent the from properly lubricating the pin?

 

Any thoughts about identifying these parts, or about honing them to fit are appreciated. I got everything cleaned up not and ready to reassemble, so i would like to move on this.

 

 

[Andydodge]

Just checked my US and Oz workshop manuals and all stated king pin bushing to be reamed to between .7960 and .7975..........so those kingpins you have are correct...........sounds like someone has installed smaller kingpins previously, tho' I've not heard of such animals being available..........is thereenough meat in the bushings to reamed them out to .7960-.7975?...........but shouldn't the new kingpin set come with new bushings to instal and be reamed to size?........................andyd 

[woodie49]

I think the issue is the support - the item in the third picture. There is no bushing for that, the king pin gets pushed through and then a metal wedge is put in to lock it in place. That is the part I think i woud have to hone out a couple thousandths to accept the pin.  I am not sure whether the knuckle would need to be also honed.  Everything seems beefy enough to accept the modifications.

[Andydodge]

The 3rd pic shows the spindle.......I've never heard of one undersize.............if the stub axles are fine and  the king pin set includes the new bushings and bearing then I'd get the spindle reamed/honed/bored out to fit the pins.........the spindle looks standard to me..............andyd

[woodie49]

It is puzzling to me how the bore in undersized. Oversized I could understand.  There is no sleeve or anything like that in it.  Similarly the bushings  (the ones installed, not the new ones) are smaller ID.  I don't know if installing the new ones and then reaming them would yield the result I need.  If the bore is undersize, I could shave a bit of the new bushing to enlarge the gap to get it to fit into the bore, but then would need to ream an extra couple thousands to fit the bigger pins.  I think there is enough bushing, but I don't know if what is left would have enough channeling to allow the grease to properly lube the joint.

Its been difficult to find a machine shop anywhere close that can even do the reaming, so, while I will probably need to ultimately trust this to someone, I would feel better with someone who understood the need for reaming in the first place.

This has to have come off of something Chrysler, Dodge, Plymouth or DeSoto related, but it seems like the Dodge and Plymouths I can find all use the same kits,  Chrysler seems completely different.  Can't find much on DeSoto.

AB has also not been able to help, because they do not have the specs for king pin diameter in their data.

Still hoping, but I may have to bite the bullet and hope I find a good shop.

I appreciate your input.

 

[Andydodge]

Re the smaller kingpins I think the commercial, ie pickups have a smaller diameter kingpin..............I do know that year for year Dodge & Plymouth standard size cars use the same size kingpin, ie .7965 from 1939 to at least 1954, maybe 1956.......however DeSoto & , Chrysler cars AND Dodge/Plymouth 7 Passenger cars all use the same larger kingpin and various other suspension parts and bushings...........but the smaller one has me intrigued?...............andyd  

[woodie49]

The King Pin package for pickups and for pre-1939 Plymouth/Dodge vehicles use a different part number at AB.  I do not know if the spindles  and knuckles look the same for any of these.  If some of you have pictures of the spindle s(called the knuckle support in the repair manual) for these models (pre-1939 Plymouth/Dodge or 1935 to 1950 pickup) I could see if these might be the parts I have and maybe a better place to focus my search on. Any help here is really appreciated. 

[Dodgeb4ya]

1948-54 light PU Truck king  pins as I recall have the lock pin locking notch flat off center on the pins.

Car pins the notch is centered.

Truck knuckles are completely different from passenger car.

A bet is that the pin lengths between car and truck are different too.

Today or tomorrow I'll measure a set of car pins.

[woodie49]

On the Plymouths, I believe the notch is off center. Attached is a picture of the pin from the Burnbaum supplied kit (the dark pin) and my old one (the light pin). It looks like the notch starts at about 1.75 inches from the bottom to about 2.25 inches on a 5.25 inches long pin. Maybe this suggests that the passenger car and truck pins are similar in design. 

My old pin looks to be made of a different material than the replacement pin. I don't know if this is meaningful. 

 

[Dodgeb4ya]

Yea..got it backwards..?whoopsie!

Edited September 10, 2020 by Dodgeb4ya

[Dodgeb4ya]

I measured a new and used king pins original #626975...

Measured the center support area..

.7945"

 

[woodie49]

Thank you so much for taking the time to do this and for the info. That is the size of the pins I have taken out of the car, so replacements of that size make sense. Although the manual says to ream out the bushings to .7960 - .7975, which seems like a lot of slop in the measurements to me. but I assume that the machine shop will ream to the appropriate pin.  I have two sets of new king pins.  One set I have had, i think, for a long time. They are .7965. Because I really am not sure where I got them, I ordered another set from Burnbaum. That arrived last week. They are identicle to those I already had, in terms of packaging, markings, etc. (which makes me think I got the first set from them as well.) They are clearly after market - in a regular brown box with a "53" stamped on them. They are also .7965.  So, the current replacements on the market are oversized? BTW, I discussed the fitment issue with AB before getting the second set.  They pulled a set for me while on the phone and measured them at ".725, or 3/4 of an inch".  I knew that couldn't be right, given that those are two different measurements for the same diameter, and seemingly well out of spec for the needed part. But they didn't know what to tell me. Ultimately, I ordered them figuring that at least I would know that I have the right set before i start altering things to fit. At least they tried.

 

Can anyone suggest an alternate supplier I might try to get a set that maybe is either NOS or manufactured in USA? Not sure where these come from, there is no marking on the box or inside to tell.  But it does seem they are too big. I also note that the set you show in your picture more clearly look like those I removed from my car. A different more shiney material and slighly different configuration to the notched area.

[Sniper]

I have a set of Delco ones for my 51, let me get them out and measure them for you. 

 

Hope you whippersnappers can read an old school dial caliper, lol.

 

 I forgot to mention that the name TRAYER is all over those Delco parts

 

http://www.trayerproducts.com/kingpins.html

 

They might have info

 

Edited September 10, 2020 by Sniper

[Jerry Roberts]

5 hours ago, woodie49 said:

Can anyone suggest an alternate supplier I might try to get a set that maybe is either NOS or manufactured in USA?

There is a set of pins only on ebay but I think that you want the bushings too .  So see ebay numbers 173240029674 and also 360810058730 for mopar sets 933435 . As you have been having so much trouble , I would ask the sellers to measure the pins before purchase . Do you have a parts list to verify the king pin set for your vehicle ? It looks right to me but you need to verify . 

[woodie49]

The part number for the set in my book is 933 435. There is no indication in the woodie suppliment that there is any other kit number.  That makes sense because so far everything north of the firewall is the same between a woodie of that year and the passenger cars.  The parts kits that i have do not reference the original part numbers, so it is not really helpful.  I have been going through EBAY, and there are a few of these sets.  So far, no one has come back with the diameter measurements. I usually avoid Ebay because i really don't always know who i am dealing with.  But sometimes you need what they have.

[Jerry Roberts]

Well if things go south on ebay you can get your money back . At least I have always been able to . It isn't always pleasant . One of those sellers mentioned that his set included pins 626975 . 

[woodie49]

Snoper - I usually consider myself lucky to be able to read the posts on the forum. Looling at your picture. It looks to me like you are at .8955? Dial definately looks to be more than half way between 90 and zero. So, probably not .8945?

 

Does anyone else have a set of pins they can check to see diameter? I am thinking that maybe the current replacements are being engineered to a larger spec. I would be interested in particularly NOS pins that might be out there.

 

[Jerry Roberts]

17 minutes ago, woodie49 said:

I am thinking that maybe the current replacements are being engineered to a larger spec

I once spoke with the owner of a large , very old alignment shop and he mentioned over - sized king pins . Like it was a common thing . Perhaps that is what you bought from AB . Can anyone else comment on over-sized king pins as replacements ?

[Sniper]

1 hour ago, woodie49 said:

Snoper - I usually consider myself lucky to be able to read the posts on the forum. Looling at your picture. It looks to me like you are at .8955? Dial definately looks to be more than half way between 90 and zero. So, probably not .8945?

 

 

 

 

.795, my dial caliper is only accurate to + or - .001".  I could have used one of my two other dial calipers, they are digital, but then I'd need to buy batteries.  The old school one doesn't need batteries, lol.  I guess I could have dug out my 0-1" micrometer, it's analog too and accurate to .0001".

[woodie49]

I have heard from three sellers on Ebay so far.  Measurements range: .795 is the lowest, .7965 is the highest.  On this forum the lowest measurement is .7945, which look like NOS pins to me. The original pin fits fairly tight - I can push it into the spindle, but need to tap it through with a hammer with no great force at all.  So, i am looking for the smallest diameter I can find.  I often keep these kinds of parts after replacement to use as sacrificial tools for other jobs.  I would like to find what the original specs were. If any of you have an old pin that you can test, I would appreciate the added data.  It may be that I really need to find NOS or decide to bore out the supports. 

 

I am surprised that there seems to be such variance in the OD of these parts, and apparently no one has experienced this issue in the past. 

[Dodgeb4ya]

I have done a lot of king pins in the smaller suspension MoPars.

Never had a fit issue into the knuckle or I beam on trucks.

The pins need to be lightly pounded into the support or beam.

I always bought new aftermarket good brand name parts or MoPar parts.

The automotive parts supply market for the last 20 years is way different....glad I don't need any of it anymore.

I don't like modifying factory parts to make after market parts fit.

JMO.?

 

[Sniper]

You know you are supposed to ream the bushings to size?  It's not a drop in install.

[kencombs]

I'm confused.  In the opening post sizes are .97xx and then lots of discussion of .79xx.  Which is the correct size range?  If it's .79something then you're only .002 off.  I'd be tempted to heat the thing up as much as I dared, then measure.  May well then be large enough to drive it in.

[James_Douglas]

If you have a set of pins in the 0.9xxx range then you have a set that is for the MOPAR Large Wheelbase cars like my 1947 Desoto Suburban or the few Chrysler, Desoto, Plymouth and Dodge Limo's.

 

Someone put the wrong parts into your box. Send it back.

 

The 1946 to 1953 MOPAR all cars Master Parts Book show the "kit" as 933-435 for 1939 to 1954 Plymouth. 

 

Now that said, I have confirmed that the Parts Books have errors or omissions on the front end parts for 1949 and 1950. Remember that it was a late and by accounts rushed change from the warmed over 1942 models that 1946 to February 1949 models represent. They also changed things a lot for 1951. So in many ways information was played with fast and loose for the si months of actual 1949 production and the 12 months of 1950.

 

I have confirmed that some spindles were used on 1949 and 1950 cars that are NOT in the master parts books. I suspect a running change or a supplier issue.

 

Almost all but the LWB cars for MOPAR during those years used a king pin that was in the 0.7xxx size.

 

One thing. I would strongly consider using torrington needle bearings in place of the bushing in the upper. It will steer MUCH nicer with them. See the attached old article. Note that the tool he made was for something other than a MOPAR so size a tool as appropriate.

 

One note. The instructions in the sheets from MOPAR with the kits day to remove all end-ply using the shims on the thrust bearings. Do NOT do that. Make sure that you have between eight and ten thousands of end-play. I found a mid-1950's tech note on the subject. Binding was an issue.

 

James

King_Pin_Bearings.pdf

Edited September 12, 2020 by James_Douglas

[Dodgeb4ya]

I think he's concerned about the interference fit into the support.

A couple thousands sometimes can be too much.

I've never tried pins that are bigger than stock.

As most know you shouldn't have to beat the pins down into the knuckle support.

Moderate quick wacks with a brass hammer.

Edited September 12, 2020 by Dodgeb4ya