Rear End Swap

I have a 63 Falcon Station bus with 170 ci motor. It only gets up to 60/65 mph on the freeway. I believe I read somewhere in the forum that you can only change the gears on the 9 inch rear end. I looked under my van and found that I do not have a 9 inch rear end. My question is if I find a 9 inch rear end from another 1st generation econoline, will it be an even swap without any customizing to make it fit?

Any information would be greatly appreciated.

That axle (the "peanut") came with two different ratios... 4.00 (common) and 3.50. I'd say try to obtain a 3.50 ring and pinion set. 9" axles are much heavier, intended for stronger engines.

If you do swap, I'm sure someone can recommend a model requiring minimal modification. Good luck.

This is probably a stupid question but with the 3.50 will it increase my freeway speeds?

yeah... fewer 3.5 RPMs of the tranny output shaft to one turn of the wheels, as opposed to 4 RPMs... 88% of the original RPMs.

it will be a little slower starting off in first, but more efficient on the highway. Instead of your engine roaring at 3000 RPM for example, you would achieve the same speed at 2625 RPM... the engine won't scream in your ear on the highway!

I'm looking at one locally equipped with a 3.50, and expect it to be very pleasant compared to the 4.00

The 9" rear axle should fit without any mods.
My friend has a '63 and installed an axle off a '66 without problems.
Just make sure the distance of the spring perches and shock mounts are the same, you may also need different ujoints to match the 9" yoke to your driveshaft (yours is telescoping, right?}

You definitely need a driveshaft with a small u- joint front and a big u-joint rear to mate up the 9 inch in place of the stock smaller rear end.

You can interchange the e brake cables from one backing plate to the other if you need to. The earlies using single e brake cable, the laters using two cables. It is much easier to simply take the cables out of yours and put them in a econoline 9" rear end if you need to. Easier than messing with the overhead e brake hdwe. No big deal. As you have the little tranny and u joint, it would be easier if you can locate a 64 or 63 H/D driveshaft. As there was no such thing as a stock big six and tranny in those yrs, they had a special driveshaft for the small front u joint and the larger 9" rear u-joint. Everything else is a no brainer swap if using our 9" rear end. MUCH stronger, easy to change third members and gearing. You can get third members all day long at pick ur parts for about $75 bucks, much cheaper than pulling your axle and rebuilding it. Go for our 9" if you can..Like posted already, 3:50's would be perfect, 3:25's too stout, 4:00's, for racing or pulling trailers only...
vic/ca
vic/ca

this is very interesting. i run with the 144 and a 4.00.1 rear end. its very punchy in low first gear but as the speed of the van increases the motor howls as the rpm goes up and stays up. it would be so great if there was an overdrive gear to relieve the motor. the funny thing is that sometimes when taking off in first gear i'll let the clutch up too fast and the van starts bucking in this pilot induced oscillation as the gas pedal gets stomped by your foot involuntarily. the other neat thing is to think that the motor has survived 47 years of this kind of use and is still going strong.

I'm looking at the same problem...I have a 170 ci &
switching out the maual transmissin for an auto...C4
small rearend..with 9" rear and 3.50 gears
I do more highway driving and that wine is just too much...
Any of you guys think the same driveshaft setup will work?

no it will NOT work. You also need to have a C4 that came from an Econoline or get the short tail shaft and short tail housing off of an Econo C4. Also not just any 9" will work. For instance a F150 9" is two wide.

Thanks Mike
That's what I like about Vintage Vans
You guys are in the know.....You've been there and done that...
These are the steps.....
Get the shift linkage and column from Vic
C4 out of an econoline
check drive shaft length small u front and large u joint in rear...64/65 econoline should work....
Question ?
Will a C4 auto work with my present '62 driveshaft/u joints setup if I put in a small 3.50 rear in the truck?

The drive shaft will need to be shortened.

Hi Primaldesigns,
Here is a repost from Fred ( fmc56) on another thread about driveshaft lengths
Art
Re: drive shaft lengths??
by fmc56 on Sun Aug 08, 2010 11:15 pm


There are several different driveshafts .
1) 61/62 one peice shaft
The rest are two peice with a slip yoke in them. The automatic driveshafts are about 6" shorter than the corresponding manual transmission driveshafts. The 63/64 driveshafts are about 1" longer? than the 65-67 ones for the same engine/transmission combo.
2) 63/64 with a 144/170 small rear axle manual transmission, two small u-joints
3) 63/64 with a 144/170 9" rear axle, manual transmission, small front u-joint, large rear u-joint
4) 64 with a 144/170 small rear axle, automatic, small front u-joint, small rear u-joint
5) 64 with a 144/170 9" rear axle, automatic, small front u-joint, large rear u-joint
6) 65-67 with a 170 small rear axle, manual transmission, small front u-joint, small rear u-joint
7) 65-67 with a 170 small rear axle, automatic transmission, small front u-joint, small rear u-joint
65-67 with a 170 9" rear axle, manual transmission, small front u-joint, large rear u-joint
9) 65-67 with a 170 9" rear axle, automatic transmission, small front u-joint, large rear u-joint
10) 65-67 with a 240 9" rear axle, manual transmission, large front u-joint, large rear u-joint
11) 65-67 with a 240 9" rear axle, automatic transmission, large front u-joint, large rear u-joint
In addition the 65-67 driveshafts for the 240's had two different diameters.
Sounds like your truck has a manual transmission and the driveshaft is out of an automatic. Measure the length of yours and the u-joint configuration and I'll see if i have what you need.
Fred

In regards to the rear end gearing, like I posted, as you have a 9"er already, that is a no brainer too easy to do,, swap out that crazy 4:00 THIRD MEMBER, BUZZING ALONG at high RPM at 60 doesn't cut it. The 3:50's are what you want, but also remember!!! its got to work with horsepower, so with that little 144 you're at a handicap no matter what you do??? its one or the other????? If you get 3:75's, that would give you a little better power range, however its still up there with the 4:00's,,, you don't have the engine power, so realize that with 3:50's, you will LOOSE some pulling power to gain some top end... that's all you can do with that motor...
You need to keep in mind that if you had the stock 144, that means its an early, which means it had the donut mount tranny mount. So this creates some problems other than easy things like drive shafts!!!!!!!!! It means that firstly for a "BOLT IN" swap you will need that TAIL STOCK. It ONLY came in 64, and not real easy to find. The 65-->67 tail stock uses a different mount, so you are limited to three combination's, as yours is an early.
First of course is the correct tail stock, 2nd is to use an adapter mount and use the late tail stock, and thirdly is to use a under tranny cross member.
There is also, two more problems. One of those is, because you have NO rear hump in the doghouse, the 64 donut mount C4 tranny, uses SPECIAL sheet metal engine hangers!!!!!!!!!!! they drop the front of the motor down, and at the same time use stud type small six mounts. The second problem is, that the 64 tranny, also, uses the UPPER bolt hole mount in the upper frame that a 64 ONLY has. You will have to drill that 2nd hole and trim the E brake and frame in order for the engine and tranny to mount correctly,, and that is also IF YOU CAN FIND the correct front engine hangers?????????????????? I have only had two sets in years that sold INSTANTLY!!!! not easy to find, let alone THAT transmission.
There is another answer to the donut mount tail, and I use them on V8 conversions in the earlies because it is actually a STRONGER mount. I sell a replacement, short tail, solid output yoke, tail stock, HOWEVER it uses the under tranny mount, much stronger. I also have in stock custom transmission cross members for sale along with this combo. They have a longer drop for a cleaner install than the shorter ones from Summit, Jegs, etc.
vic

I had a 170/3spd/7" rear and could not only keep up with Chicago traffic on the interstate (the slow cars are going faster than 65mph!) but pass a lot of cars. I know I could pull 70-75 without a problem. That makes me think you may have a problem beyond your rear gear ratio. BUT, I don't know how fast I was really going because my speedo was not accurate... because I had much taller than stock rear tires.

Instead of trying to mess with swapping gears on the already weak 7", or swapping in a 9" and trying to find a rare drive shaft (or having one built -about $300), you could change the rear tire size which will effectively change your rear ratio. If you found good used tires it could be a cheaper short term solution

Changing tire sizes in order to change gear ratios to me makes no sense what so ever???? Putting larger tires on it to gain some top end speed and cruising with a jacked up rear end stance?
It isn't true that you cannot change gears in the peanut rear end, you can, but it is the same as a complete new rebuilt rear end when you do and still leaves you with a weaker unit, and you are stuck with the gear set you put in UNLESS you drop the whole rear end and if it rebuilt all over again with a different gear ratio??
There really is nothing as good, as easy, or as strong as a simple Econo 9' rear axle. If you decide to change engines or don't like the present gear set, its as easy as dropping the third member and slamming another one in with a different gear ratio......
With a small six or any engine of lessor horsepower, of course you're pick of gearing will be much more critical, as you don't have the extra grunt to pull a wider torque range with any gear set,,, you can't have it all. What ever your choice is, its gonna be a compromise of pulling power versus high end cruising speed and gas mileage,,,,,
vic

Changing 2 tires for a slight rake and change in highway RPMs is a lot easier than finding a 9" with the right width and gear ratio (or changing what's in it) and then either finding that rare 170-to-9" driveshaft (or paying a few hunderd to have one built from scratch). Finding another 7" with the right gear ratio (1 of 2 made?) seems like a lot of work... at least a lot more than just changing tires.

It's not the only way to go, but it is a cheap alternative that will work. It's also one he could undo easily.

FWIW, I have 205/75/14s on mine and the rake is not that noticeable, but I had no trouble on the highway with a 170/3spd/7". Maybe it wasn't the tires. Could have been the rear ratio. Or he has carb/ignition trouble or something.

Just trying to offer some solutions.

need a 7 " rear?? ive got 2

Hang in there. I just did this swap today. 170 w/peanut to 170 to 9". Did some searching and found the small to to big drive shaft.

in the case where swapping to a 9" rear just isn't feasible, can we put together some collective knowledge on where to find 7" ring & pinion sets that fit our vans? i've seen that ford used a similar rear end in some of the 80s and 90s ranger trucks, but i doubt they are interchangeable. most of the junkyards in my area have a wealth of late 70s through 80s to mid 90s ford and other domestic vehicles. what would work? internet searches for r & p sets turn up nothing but high ratio sets (which is my original problem).
i know the 7" sets are weak and all that, but i seriously just want to cruise in my van, nothing more.

thanks!