Wondering if anybody can give advice on swapping the stock 3 speed and banjo rear on a 48 Tudor to a 49-53 3 speed OD and rear end. Will the 49-53 trans mate directly to a 59AB? I assume the X member would need to modified? Will the 49-53 rear end fit without mods or is it too wide? Where could I find the specs on a 46-48 & 49-53 rear axle?
The first 2? years of that transmission had the half bellhousing like the 39/40 transmissions, so they should bolt right on. The later models would need that half-bellhousing adapter piece which houses the clutch fork. Probably easier to get an open shaft kit for the rear, and reinforce the radius rods a bit. The x-member may need notching out - possibly floor, and a tranny mount welded or bolted in. Get the pieces and line them up and it will be obvious. TP
If you are getting everything, you may need the clutch parts too, the way the clutch works may also be different. Linkages. I'm building a 30 AV8, and using a 53 ford truck engine, clutch and transmission all connected to a 50 ford rear end. The drive shaft is different, the linkage for the clutch is very different. Its been a tough job getting it to work. I'm using 50 ford foot pedals, they are not even similar to the 53 truck linkage. If you are getting parts out of the Mercury, then my advice is to get everything.
I did a similar swap on my '47 coupe a few years ago. I did not use the OD trans, just a standard '49/'50 (& early '51) 3 speed. The trans is a bolt in as far as the clutch splines, bellhousing pattern, and clutch linkage are concerned. I did swap the side plate to keep the stock '47 shift arms as they differ on the later Merc unit, but the side cover is a direct bolt on. For the X member I did the following. I drilled out the rivets holding the lower reinforcement plate and removed it. I also drilled out and removed the rear trans mount from the X member. I fabricated a new trans mount and installed it in the X member...then reinstalled the lower reinforcement plate, all with grade 8 fasteners. Of course I had a new driveshaft made up to connect with the 8" Ford rearend I also installed at this time, using a Chassis Engineering parallel leaf kit. Since I did not use an OD, I can only speculate that it will cause some clearance problems in the X member. It's pretty narrow in there and with the governor and solemoid, things will get tight in a hurry. I can only suggest you make careful measurements and see what you come up with. Oh, by the way.....I did this on a fully assembled vehicle, not a bare chassis. On these cars, as you may know, to pull the tranny without removing the engine, you have to remove the floor board (it unbolts) and remove the trans from the topside. And, of course, the replacement goes in the same way. That OD unit will very likely make that a much more difficult proposition as well. It is likely that I had to slide the transmission into place before final installation of the newly fabricated mount and lower plate. I am not taking issue with use of the OD. That is desirable. Only saying it makes a very simple swap a bit more complicated. Best wishes on this project and keep us posted on the progress. Ray
According to the info I pulled off the H.A.M.B. years ago, the '42-'48 Ford rearends were 61" WMS-WMS.
Great information guys. Thanks! This will be something new for me as I've done some stock rebuild stuff before but never swapped out major components. If anybody else has any info, I'm all ears. It will be a little easier during mock up as I have a bare frame to start with so I can monkey with it top side and bottom. BTW - WMS to WMS. Gotta be something like drum to drum but what exactly is the acronym? Thanks again! Ron
WMS = wheel mounting surface to wheel mounting surface........the only ACCURATE AND USEFUL way to measure the width of a rear end. Some guys talk about 'flange to flange" and that usually means the axle HOUSING width, flange to flange, not the axle shaft flange to flange. Using the housing width makes guesswork out of the actual width as brake backing plate offset and drum width are variable and determine the useful width of the axle assembly. Ray
Thank you for your insight and explanation Ray. Makes sense to go with actual mounting surface as opposed to flange or backing plate dimensions. Have the frame, a line on a stock front end, and trying to gather up the trans, drive shaft and rear end. Hope to get going early in the new year.
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