It all started a couple years ago with the purchase of a 46 open drive banjo out of a 46 1/2 ton. Didn't have a use for it, just got a deal on it. I stashed it in the corner of my garage for safe keeping. A couple months later, I noticed that there was a complete model A rear suspension sitting next to it. A couple months after that, there was a 40 closed drive passenger car rear sitting on the pile, too. Enough is enough! I decided that something had to be done before they took over my garage! I needed a rear end for my flathead/T-5 powered T, so I decided to use all three to make one. All I'm doing is mocking one up, I'll set it up after it's painted up. For once, my camera was in the shop and I thought some one would be interested in the process performed by a first timer like me. Here is what I started out with. The 40 pass. car rear is in front with the open drive bringing up the rear. I started by using my bearing seperator and steering puller to pull the drums. Next, I removed the 40's spring: Using my trusty cordless impact, I removed the housing to center section bolts(make sure you save these) and pulled the axle housings off. MMMM, smell that 60 year old lube! I cut the saftey wire from the carrier bolts and removed the nuts. I then gave the ring gear a light tap with my rubber mallet, and pulled free one axle and the ring gear. I started pulling a part the carrier to get the other axle free. Now, I pulled the axle through the disassembled carrier after removing the spider gears. Do yourself a favor, and wear some rubber gloves. I repeated the steps on the oped drive. Unfortunately, the drums on that rear were froze on, so I torched through the 1/2 ton housings and axles. MMMMM, burning 60 year old gear lube! When I was through, I ended up with this: The open drive threads are covered with green tape, the closed drive splines are covered with a hose. I then started the reassembling process, using the open drive center with the 40 passenger car axles: Drop in the axle Install the spider gears: Install the other axle : Tap the carrier bolts through, and install the nuts: This was the easiest way I could think of to get the axle/carrier assembly into the center section and axle housings. I clamped one housing into my free standing vise. I also ratchet-strapped the housing to the vise. I then slid the axle into the housing. At this point, I decided I wanted the spring infront of the rear, so I orientated the center section accordingly, bolting it and the axle housing together. I then slid on the other axle housing and bolted it to the center section: And there we have it! I later bolted on an A rear spring, which kind of sucked because I couldn't use my spring spreader beacause the pinion yoke got in the way. So, I installed the bare main leaf and put a long piece of all thread through the spring bolt hole. I then dropped on the appropriate number of leaves(four), tightened it down, clamped the spring pack, pulled the rod and installed the spring bolt. I'm sorry I don't have pictures of this stage. Well, there it is. Like I said, this is just a mock-up to set-up the car. After the assembly gets blown apart for paint, I plan on using the-rodster's post in the Tech Archive to set-up the rear.http://www.jalopyjournal.com/forum/showthread.php?t=61502 Karl
Good Ford tech! Some related stuff: All '355-48 rear stuff can be swapped, but there are some wrinkles. There are two tooth counts of spiders, changing maybe about '38, so if they don't match just put all the right cogs from the donor rear into the differential case you are going to use. Very often Ford gears and bearings are good to reuse, a damn good thing because they are expensive to replace. I recommend swappin around used bearings and races TOGETHER. If they've been a happy couple for 60 years, don't mess with'em. SO if you swap housings from side to side or with a different differential, pull either the bearings or the races and put them back on the side with their old mates--what you pull likely will depend on what tools you have. If keeping most of a basic assembly together, SAVE a section of gasket from each side of banjo to measure. Used gaskets normally measure about a thou under new, and this way you can tell what thicknesses were used to set the thing up originally. This will probably put you way ahead at setup time, when the gaskets are used to set mesh and end play on a Ford.
Karl... I'm glad you posted this because I am about to perform this exact process. I recently picked up the '46 open drive banjo and have a '40 banjo that I need to swap pieces and parts on. Is there a torque spec for the yoke pinion nut? I don't have any literature at my dispossal on setting these banjos up (except the HAMB). Thanks... and good tech! Alec.
I'm at work with no books, but this from the flathead technosite is pretty good: http://www.btc-bci.com/~billben/rearend.htm Basically, on the pinion you tighten the inner nut til you get specified drag. Set this on the tight side. Then with two wrenches you tighten the outer nut against the inner and bend up the lock tabs. Pinion depth was not adjustable, the Ford parts were supposed to be held tight enough for everything there to end up in the right place in the matched R&P set. Recent repro gears may well need adjustment, in which case you get to invent your own way to shim or cut things.
Open drive axles '42-47 are same as '42-8 passenger--and are somewhat longer than earlier bits. Axles and housings can be freely swapped together as needed, with above proviso re spider gear types.
The open drive pick-up axle housings were an inch longer per side. Yes, make sure you use the 40 housings AND axles. 3blapcam, I have no idea of the official torque rating for the pinion nut. I'm stilling digging around to see if I can find it. I guess I usually just nailed them with my impact until they "felt" right. Karl
It isn't torqued like a rear with crush sleeve--the inner nut gets tightened until TURNING torque is as above, then second nut and tab washer secures it at that setting. It's much like setting front wheel bearings, but a bit tighter.
But, the only purpose of the pinion nut(or I guess you'd call it the "yoke" nut )on an open drive banjo is to hold the yoke to the pinion. The preload of the pinion is already preset by the inner and outer nut. If you look, the yoke comes nowhere close to the inner and outer nuts. I agree that preload adjustment requires some delicacy. Karl
I see now! Sorry, I forgot this wasn't a torque tube rear. That nut doesn't exist in my part of the planet. I'll check and see if I can find a source for a number on that, but if not I think giving it a good jolt with the air wrench will do the job just fine...
I can't find a damn thing in the first 500 pounds of USA and Canadian Ford books I went to--the Canadians had even confused the axle ID, and put the big 3/4 ton axle in the specs column for commercials. I don't think there's a readily available spec, so tighten it til it strips and then back off 1/2 turn!
GOOD TECH i read an artical in Street Rodder that went through all the banjos with all the differences and such it had a parts list and year designations i can't remember the year or month but it was there tom
There is a big part that I missed. The ring gear clearance and bearing preload is set by the gaskets on the sides of the center housing. This is a delicate process and takes much care and experimentation. There is a spec. for the gear clearance that is set with the gaskets. I think it is .018 but it has been a while. You can't just put in gaskets and bolt it down.
Some info on the settings is in the link above, more in Rumbleseat's flathead onlinr book... Basically, you first choose a total thickness of the two gaskets to set proper load on the carrier bearings, that is the total width needed between the two bearings. Then you need to set clearance between the ring&pinion by further adjustment--you keep the total gasket package the same, but subtract thickness from one side and add the same to the other until lash between the gears meets spec. The pinion preload is set by tightening a big nut on the pinion to set load on the paired bearings, then locking this setting down with second nut and tab washer. I strongly recommend buying a manual or two on this. Also see my note above--unless all is new or swapped, keep samples of original gaskets so you have a baseline!! Books available in current catalogs to try: 1928 or so service bulletins, basic setup of Model A banjo. 1933 Service bulletins--setup of straddle mount banjos. Crank'n'Hope pubs 1939-48 manual, actually a 1946 Canadian shop manual 1942 Ford Army staff car shop manual--EXCELLENT, available from http://www.portrayal.com/ military reprint source A selection of the above will give you a pretty good early Ford shop manual. There are also a number of early books written for garages that are useful if you can find them.
Here's a link to the "Gears" chapter of the Rumbleseat book: http://www.flatheadv8.org/rumblest/gears.pdf
So... yeah, I'm bringing this back to the top... because I started to tear into my open drive axle. Well, let me say first off, that I don't need to know the yoke nut torque spec because I don't have that nut. Apparently, someone didn't like it and decided to weld the yoke to the pinion. I'm really excited about that by the way. That leads me to why I am bringing this back up. I was wondering if that rear axle has "special gears" or if it's the 6 spline with an adapter? I don't have the yoke off yet, but I have another yoke and it doesn't have splines inside. I have 2 other torque tube type axles and was wondering if I can use those gears, or I have to search high and low for new gears... then sell my soul to purchase the damn things. I'm sure the gears are trashed because "backlash" on the welded pinion needs to be read in the 100 thousandths ranges... and not the ten thousandths since I don't think this one was setup using the Ford Manuals. Thanks for your help and insight!
The yoke for your open-drive banjo has a tapered/keyed bore similar to the axle/brake drum connection.....no splines there. You can't use the torque tube pinion gear unless you want to spring for that $275 conversion kit. I still need a yoke.
I've got a yoke and a half at this point... where do I get gears? Maybe you and I will have to make a deal?
The pinion gear is unique to that open-drive setup. No torque-tube pinion will do it without being adapted. There was a thread here awhile back that showed how to make your own seal adaptor to use with a splined pinion. Not real complicated. The open-drive pinion will be hard to find. I have the hub portion of the yoke but the forward/bearing-saddle portion is rotten from laying in mud and water for 50 years. I have no extra parts.....just cash and not a lot of that !
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