Are M5 and '39-'46 Champ steering boxes same as old Jeeps?

[Gary_Ash]

I'm cross-posting this from the Studebaker Truck Talk forum to see if it would stir up any interest from the '39-'46 Champion crew.

Over on the SDC site, someone asked about parts for an M5 steering box made by Ross. There were a couple of responses. I mentioned that the 5/16" balls, cups, bushings, seal, and sector arm looked a lot like old WWII Jeep GPW, MB, and CJ2/CJ3 parts - all of which are available from Jeep parts sites. Bo Markham doesn't think they are the same, but chime in here, Bo. So, who has a steering box from an old Jeep that they can take apart and check? If the parts are the same, it would make it easy and cheap to rebuild M5 and Champion boxes. Note: these comments do NOT apply to M15 or M16 steering boxes or Commander/President cars!

Here's what I am pretty sure of:

Bronze bushings: listed as 197104 and 197105 in the M parts book, can both be replaced by Studebaker part 680211, readily available through SI, etc.. These are 7/8" i.d., 1" o.d., 7/8" long Oilite bushings, available through many bearing shops as EP141614, SAE type 841 oilite bronze. Price $2-$5 at various sites, especially as EP141614.

Arm seal: rubber with steel shell, Studebaker p/n 517090, shell stamped 120N056GK or 120N056W. Can be replaced with NAPA seal NOS8645 or SKF8645 or similar. The original ones were leather seals, newer ones are rubber. Dimensions are nominal 0.875 i.d., 1.312 o.d., 0.25 thick, $2-$4 at various sites.

Here's what I would like to find out:

Bearing kit, Jeep part 646084, consists of two cups plus 22 balls 5/16" dia (11 per cup). I took apart an extra M5 box I have. The M5 cups measure approx. 1.718 o.d., .33" deep, hold 11 balls. I think the Jeeps cups and balls will fit the M5 box, but it needs to be confirmed. Walck's Jeep has them for $10.45 for the set. These would replace Studebaker parts 197101 (Cup) and 470-10 (5/16" balls). In the M5 box, the lower cup also seals the bottom of the box. The steering shaft is hollow all the way through so that the horn wire exits through the shaft and cup.

Steering Gear Cam Lever Shaft (Sector Arm in Jeep-talk), Jeep part 805123, consisting of new sector shaft, 2 bushings, and seal. Walck's carries this kit for $74.95. Both the Studebaker and Jeep parts have 7/8" o.d shaft. The difference, if any, might be in the length of the shaft. The M5 part I masured is about 6.5" long from the outer tip to the end of the 7/8" dia shaft where it hits the plate that holds the two pins. I guess I'm not ready to send $75 to Walck's to find out, if only because I don't need to rebuild my M5 box. But one of YOU does! Or you have an old Jeep GPW/MB/CJ2/CJ3 box lying around to check. This would replace Studebaker part 197102 in M5 trucks and 1939-46 Champion cars. I'm betting that Ross used the same parts for everyone.

Worm: I'll bet that the worm in the Jeep box is the same as the Studebaker one. The M5 worm is 1.375 o.d. has 4-5 turns. It's stamped T123034 NE 1 in the M5 box I have. There are replacements available for Jeeps, but they are different lengths from the M5 shaft (49.5" end to end). In a pinch, it should be possible to remove the old worm from an M5 shaft and maybe replace it with a Jeep one. It's not clear to me how to do this.

Anyone got Jeep parts or a need to rebuild an M5/Champion box?<!-- google_ad_section_end -->

Photo below is the inside of an M5 box.