I searched the forum and couldn't find a thread about this already so, what is the width of a 40 rearend? And why does everyone prefer them? Is it the fact that they measure good under a highboy Model A or 32? I have a rearend sitting in pieces and want to see if it's a 40. Thanks in advance.
1940 rearend width measurement
- Thread starter pharaoh41
- Start date
rotorwrench
Well-known member
They're about a total of 2 inches shorter from tip of one axle to tip of the other axle. It just keeps the tires a little closer to the body without messing with back spacing of the wheels.
Kerby
Kerby
Flathead Fever
Well-known member
The forty rearend is a slightly better rearend. As the cars became heavier Ford beefed up the housings and spring hangers (I have a ‘33-34 rearend that has a cracked spring hanger) The ‘40 rearends have a much stronger spring hanger. I was told by an early Ford rearend specialist that the ‘32 to’34 carriers (the part the ring gear bolts to crack). I have several ‘33-’34 rearends and sure enough, one of them that I disassembled had a cracked carrier so it must be a fairly common problem. The later rearends have slightly stronger carriers, these carriers will work in the late ’32 to ’34 rearends. Another neat feature of a ‘40 rearend is the aftermarket tube shock mounts that bolt to the backing plates. They are a great way to bolt tube shocks on the rear of a ‘32 without having to do any welding on the housings which will warp them These mounts will not fit a ‘32-’34 rearend because there is not enough room between the spring hanger forgings and the backing plates. The forty rearends came with hydraulic brakes with the small bolt pattern that would except the stock ’40 16” rims or the 35 Ford wire or Kelsey rims, (spacers are required for the wires to support the hub unless you use ‘35 rear drums) The ‘39 rearends with hydraulic brakes have the wide-five bolt pattern so you would need to swap out the drums, otherwise the rearend should be the same as a ’40. ‘46 to ‘48 rearends are a little too wide for a ’32. Some guys used them on channeled cars to keep the tires from rubbing on the quarter panels. ‘35-’36 rearends also make nice rearends for a ’32, they are my favorite looking rearend in a '32.
The ‘32 to’34 reraends have a compound curve in the spring that fits into a cross member with a matching curve. The ‘32 spring will not work with a ‘40 rearend because the ’40 spring hangers are longer. Most guys grind the ‘40 spring to fit the ‘32 rear cross member. Some guys cut the rear cross member and straighten it and then weld it back together. If I had a pristine ‘32 frame I definitely would not cut it.
With all that said the stock ‘32 rearend fits without doing a thing to it, there is a lot to be said for that. The late ‘32 rearend with the strattle mounted pinion gear is preferred but they are really hard to find. The ‘33-’34 rearend is the same rearend except you will need to shorten the torque tube and Driveshaft (speedway has a driveshaft kit) I would run the stock Houdaille hydraulic shocks with a ’32-34 rearend since they bolt right up. The only down side to these skacks are they are a little pricey to rebuild. They look good on a 40s era hot rod.
The ‘32 to’34 reraends have a compound curve in the spring that fits into a cross member with a matching curve. The ‘32 spring will not work with a ‘40 rearend because the ’40 spring hangers are longer. Most guys grind the ‘40 spring to fit the ‘32 rear cross member. Some guys cut the rear cross member and straighten it and then weld it back together. If I had a pristine ‘32 frame I definitely would not cut it.
With all that said the stock ‘32 rearend fits without doing a thing to it, there is a lot to be said for that. The late ‘32 rearend with the strattle mounted pinion gear is preferred but they are really hard to find. The ‘33-’34 rearend is the same rearend except you will need to shorten the torque tube and Driveshaft (speedway has a driveshaft kit) I would run the stock Houdaille hydraulic shocks with a ’32-34 rearend since they bolt right up. The only down side to these skacks are they are a little pricey to rebuild. They look good on a 40s era hot rod.
334charlie
Member
41 to48 rears are aproximately 2" wider
19Fordy
Well-known member
Please let us know. And while your at it measure the width of the stock 40 front wheel mounting surface to wheel mounting surface. An easy way to do it is to use hold a wooden paint stick in place on the drum using an upside down lug nut. Then measure to the ouside of each stick and subtract the thickness of the stick times 2.
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chrisgurga
New member
any one have a decent frame for sale for a 1940 ford coupe reasonable near south carolina i have 2 rotted ones now have a 59 ab flathead complete with aluminum intake and stromberg carb not sure if turns sat 40 plus years in car out side stock trans front and rears to sell or trade need coupe doors also my car is very rusty .i would like to use mustang front and leaf rear maybe nova ???? not sure what fits any help is appreciated chris@gurga.com
