Pinion Yoke, Long vs Short

[basstrix]

1. Besides slip yoke engagement/driveline length, is there any reason I cannot use a 4" (short) yoke in place of a 5" (tall) yoke?

2. Do any of you know who sells the 1310BC tall yoke?

I was wrapping up replacement of extension housing seal and bushing when I discovered the rear u-joint fit the pinion yoke with quite a bit of slop. I have a driveline vibration that comes and goes and I suspect this is either the cause or result of it. In any case, it needs to be fixed.

From my searches, some of our models came with a 1310BC Tall/Long yoke. This is a yoke with 1.125" diameter caps, hence the Big Cap notation, 3.220 (aka 3.25") wide cap to cap, and a 5" tall overall height (trunnion center to end of yoke). Evidently, my yoke is worn to a width of 3.288". I searched a number of different u-joint and yoke suppliers and none show this width, so I've concluded my yoke is worn.

My next step has been to search for a replacement. The combination of BC and Tall tends to confuse the search. I am able to find the short version with correct width and oversized caps, but thus far, not the tall version....which is why I've asked question #1. As a side note, I have considered going to a 1330 yoke and u-joint, but I have a 4.30 differential with traction loc that also uses the 1310BC yoke. This would leave me a headache when I swap diffs. My first choice is to find the 1310BC Tall. I can use the short version, but then the slip yoke ride differently in the trans bushing when I swap to the 4.30 diff.

Happy New Year!

 

[mjlan]

I think changing yoke length would require getting a new driveshaft made.

Strange Engineering or Yukon Gear should be able to provide a replacement yoke with the correct joint specs and the same length.

 

[Sheriff41]

I use Denny's Driveshafts for replacement yokes. They have a good inventory, good prices and quick service.

 

[basstrix]

I think changing yoke length would require getting a new driveshaft made.

Strange Engineering or Yukon Gear should be able to provide a replacement yoke with the correct joint specs and the same length.

When I switched from an FMX to C6 I shortened the drive shaft by the "prescribed" amount....still, my slip yoke is pushed deeper into the trans than with the FMX, thus I believe I have enough length available, but still need to measure and validate that statement.

I've searched Yukon Gear's website to no avail, but I may give them a call or email them direct...perhaps, they don't list this oddball yoke. I've briefly looked at Strange's site, but haven't scoured it yet.

 

[basstrix]

I use Denny's Driveshafts for replacement yokes. They have a good inventory, good prices and quick service.

I just emailed them. The 1310BC yoke is not listed on their website. Incidentally, their description was one of the more informative on the hybrid 1310 u-join/yoke Ford uses.

 

[tony-muscle]

Couple options but better talk to them:
https://www.dennysdriveshaft.com/p1...kit_1310_series_28_splines_5_inches_tall.htmlhttps://www.quickperformance.com/Ford-9-1310-long-Narrow-Billet-Yoke_p_21522.htmlhttps://www.currieenterprises.com/CE-4042L

 

[boilermaster]

Basstrix,
is your current driveshaft 2-3/4'' or 3'' ?
Some of the FMX driveshafts were 2-3/4''
Guessing that is why it hard to find a 1330 type yoke to suit your needs.
You should be using 1330 type u-joints and yoke with C-6 and 4.30 gears as well as the Daytona ( big bearing) pinion support.
Most of our cars that came with 3.50 or higher (numerically) used a 1350 type u-joint and big bearing pinion support.
My 1973 Q (4 speed) 3'' driveshaft 1350 joints, 3.50, 4 pinion open diff with nodular diff and Daytona pinion support.
Unless you are running a 302 or stock 351 2v, you should be running the beefier parts.
Boilermaster

 

[basstrix]

I just measured...2-3/4. It's originally an H code, so that makes sense. I didn't realize there was a different driveshaft diameter. Does the 3" use 1330 joints front and rear? I've always intended to upgrade the drivetrain but never have prioritized it....used to run this driveshaft behind a 429 and later a 460...with drag slicks even! Guess I was living on the edge of disaster.....glad I never had to make use of that driveshaft loop!

I recon this will put some priority into some upgrades...glad you mentioned the driveshaft diameter.

 

[boilermaster]

Basstrix,
Use the search function, type in driveshaft.
You will find C4/FMX driveshaft Sept 10,2021
post # 5 Hemikiller has provided an adobie attachment, it lists slip yoke, driveshaft and u-joint dimensions for mustangs thru 1972.
There was even a 3-1/2'' driveshaft for 351w C6 and 429 4 speed mustangs.
This is where I figured out how to use my stock length driveshaft for my TKX swap using a super short
Daytona yoke and determined what conversion 1350 and 1330 u joints to use.
Boilermaster

 

[Hemikiller]

 

[mrgmhale]

View attachment 71577

Another useful image from HemiKiller well worth saving as part of my ever larger library. Many thanks.

It may not be of help within this initial subject for thread, but just something to tuck away somewhere for future reference... On our 73 Mach1, which originally came with a 302 2v and C-4 auto tranny, the prior owner swapped in a 351W (not C) and built it up for moderate street/strip performance (dyno shows 360HP, decent for an 9.5:1 compression ratio for use with 89-90 octane fueled non-ethanol, regular fuel). At the same time he changed the 2.79:1 rear axle gears to a 3.5:1 TractionLok unit.

The other year the C-4 began to slip in its 1-2 upshifts at WOT, whereas before it began to slip it would spin the tires on the 1-2 upshifts at WOT. So, clearly the intermediate band, at a minimum, was having problems - more than a simple band adjustment would help (it had been rebuilt about 1 1/2 years prior, using high performance internals, and had less than 800 miles on the tranny). Rather than re-rebuild the C-4 (again) I decided to swap in an AOD. I ordered a unit from Monster Transmission upon the advice of a local shop, and ordered the option for a firmer than factory level shifting. I ordered all the adapting parts my research indicated I would need for the transplant into a 1973 Mustang.

For our AOD transplant project I found the distance from the C-4 output shaft to the rear axle pinion flange was just a little less than 1/4". In looking at the front yoke I saw there was a little over 1/4" of additional travel of the slip joint part of the yoked, where the C-4 tailshaft oil seal had not travel across and kept polished down. I cleaned and polished off that previously unused part of the front yoke, making certain the front yoke could travel beyond the part that never slid further forward into the C-4. Then I installed the driveshaft. The front yoke slid onto the AOD output shaft perfectly, and the rear axle oil seal also fit perfectly.

Being that I had read, several times in different articles, how I could expect to need to alter the length of the driveshaft I was curious why I did not need to make any alterations to ours. It turns out our AOD had an optional short output shaft and output shaft housing. The short output shaft was apparently used for trucks with 4 wheel drive transfer case. I had not ever considered the possibility the AODs had different tailshaft extension lengths. Otherwise I would have specified the short tailshaft length. In my case we just got ******* lucky.

As for the speedometer output gear, you will likely need to replace your output gear. I did not have to change ours as we have a Dakota VHX analog instrument instrument panel. I was able to calibrate our speedometer electronically through the Dakota setup options. You will need to do a little electrical fabrication for the AOD Neutral Safety/Backup Light switch (NSS/BUS). It is truly very easy to do. In my attached documentation I show where I ordered my custom pigtail from (Summit Racing), and show how I spliced the new pigtail into the switch side of the NSS/BUS used with the C-4 transmission. No modifications were needed for the vehicle's electrical harness. Just to be very clear, all changes were made on the switch's harness side, where I cut off the plug side of the C-4 NSS/BUS and spliced it into the new pigtasil for the AOD NSS/BUS connection. And I took the time to solder the electrical splices and used shrink tubing to protect the splices, although using simple crush connectors would have technically worked - until road grime and general corrosion begin to act on the connection points. We do not drive our pony cars unless the roads are dry, but I still opted to solder the spliced connections anyway. Here is the YouTube video on that part of the transplant, just to help allay any concerns about how hard it is (it really is easy, really, it is):

https://youtu.be/zzDmFjFfT-A


If anyone is interested in an AOD swap I have attached some files. which contain my parts vendors and parts listings. Within one of the files are some YouTube links for the entire transplant process plus showing how to adjust the Throttle Valve Pressure cable properly (if the Throttle Valve Pressure is too low it can result in your AOD clutch pack friction surfaces becoming fried). If anyone has questions about the AOD transplant please feel free to email me at [email protected]. That said, the attached files and YouTube videos ought to clear up any mysteries.

The AOD transplant is an upgrade I would definitely recommend, especially if you have rear axle gears that are 3.5:1 or lower - especially if you have 4.11:1 or 4.88:1 gears. If you have a lot of power from a highly modified engine select an AOD that has been built with high performance internals, and a performance oriented shift kit for the valve body. The AODs can be built to be rugged, but do not expect it to ever be as strong as a C-6. Personally, I would not use an AOD with anything over 800 HP no matter how well it is built. Even then I feel the AOD would be at the far edge of its durability. For high horsepower/torgue engines you may be better off with a C-6 and adding a GearVendors overdrive unit. https://www.gearvendors.com/f2wd3s.html