8.8 to 9" swap info on driveshaft and u joint

[shockseals.com]

Details:
1996
5.8L
4spd auto
Electric T-Case

Factory Driveshaft from U joint centerline to first u joint centerline on double cardan(basically not account for CV and flange(4.5") or flange at pinion(1.5")
20 9/16 Min
24 11/16 Max

Why did I measure that way? Its easier to measure it accurately since there is no angle to work with.

With 9" installed at 25.5 degrees pinion angle and roughly 4" of lift
Fully Drooped (0" travel) 23.5" U joint to u Joint
Ride Height(9" travel) D-shaft measurement: 23" u joint to joint
Fully Bottomed D-Shaft Measurement(16" travel): 21.75" U joint to u joint

The rear u joint if you run a 1330 Yoke is the same U joint as the two front driveshaft u joints. 3.625 Wide with 2x 1.0625 and 2x1.125 caps
Spicer good stuff is 5-792X or parts house cheapo is 434.

Stock driveshaft works just fine. I would only suggest paying to have it made or making it an inch longer yourself if you have a lot of horsepower.

Mark @ southwest has the nicest VSS relocator. Install it with 12pt head bolts and carry a spare driveshaft flange or nuts for the said bolts above so if you have to remove the rear d-shaft and drive with front wheel drive you can fasten the ring down instead of having to pull the flange off the T case to remove the ring.


Hopefully this info benefits somebody doing the swap. I only found ambiguous half ass info on the web which is why I hope to save somebody else the frustration from lack of info on something lots of people have done or want to do.

[tcm glx]

Kris, this is great info, I plan on doing the swap eventually. Question for ya... You say the rear yoke is a 1330, that is the same size as the stock driveshaft isnt it? SO basically, just remove the flange adapter off the factory driveshaft and run it straight to the 9"?

[SteveG]

Thanks for the info, Kris. That's all good stuff.

[philofab]

Kris, this is great info, I plan on doing the swap eventually. Question for ya... You say the rear yoke is a 1330, that is the same size as the stock driveshaft isnt it? SO basically, just remove the flange adapter off the factory driveshaft and run it straight to the 9"?

You take the flange off and bolt it right up to a truck 9" yoke. Be aware that 1310, 1330, and 1350 yokes are available for 9" pinions.

[shockseals.com]

Kris, this is great info, I plan on doing the swap eventually. Question for ya... You say the rear yoke is a 1330, that is the same size as the stock driveshaft isnt it? SO basically, just remove the flange adapter off the factory driveshaft and run it straight to the 9"?

Its called a 1330 "special". Its common by Ford. It uses 2 X 1.0625 caps and 2x1.125 caps.

If you just yank the flange and slap it on a 1330 yoke you will destroy the yoke eventually and probably have vibration issues. Its easy to miss too. If I didnt have the parts on the bench to test fit I would have missed it because I am not familiar with Ujoint to yoke "fit" and it looks like it fits.

You could just take the caps off of a 1330 with the larger caps and toss them on the factory u joint but I dont recommend that considering a good U joint only costs $25 and takes about 10 minutes to swap.

You can see the "special" here:
http://www.actionmachineinc.com/ujointm ... guide.aspx

[tcm glx]

Ok, so I think I got it.

Let me se..... so instead of keeping the 1310 u joints on the DS, you use that 1330 special, which keeps 1310 size caps on the DS, and the 1330 caps on the Yoke?

[shockseals.com]

Ok, so I think I got it.

Let me se..... so instead of keeping the 1310 u joints on the DS, you use that 1330 special, which keeps 1310 size caps on the DS, and the 1330 caps on the Yoke?

The u joint is a 1330 stock it just has different caps. The series refers to the width most importantly a 1310 is narrower...

When you order u joints always order by width and cap size then you will never be wrong.

I dont see any reason to go to a 1350 unless you have over 400hp and going to a 1310 would be silly. A 1350 would require a "conversion" u joint if you wanted to keep the stock driveshaft and run a 1350 yoke.

The "special" 1330 is not a conversion joint its just what Ford decided to do.

[tcm glx]

Ok, so I think I got it.

Let me se..... so instead of keeping the 1310 u joints on the DS, you use that 1330 special, which keeps 1310 size caps on the DS, and the 1330 caps on the Yoke?

The u joint is a 1330 stock it just has different caps. The series refers to the width most importantly a 1310 is narrower...

When you order u joints always order by width and cap size then you will never be wrong.

I dont see any reason to go to a 1350 and going to a 1310 would be silly. a 1350 would require a "conversion" u joint if you wanted to keep the stock driveshaft and run a 1350 yoke.

The "special" 1330 is not a conversion joint its just what Ford decided to do.

Got it (I think). Not planning on going with the 1350, but Yukon might be tossing me a fully built 35 spline 3rd member with their version of a detroit and corresponding 35 spline axles. Now I just need a 9" housing.

[shockseals.com]

have them set it up equal length so you only need 1 spare axle.

[Rwies]

Are the factory Bronco 9" rears equal length?

[Deleted Account]

yes they are

[philofab]

I will have to check my u-joint now. That might be the slight vibration I get over 80 mph.

[shockseals.com]

I will have to check my u-joint now. That might be the slight vibration I get over 80 mph.

dont wreck your yoke!

[Big Bastard]

Hey guys I have the opposite circumstance. I've got an 80 F 100 Flareside 2wd (Clapper 8) that I am building. Auto Fab Bent Beams in front, still figuring out the rear. I'll be taking it to Nichols Fab in Tucson for the rear suspension work and a lot of other stuff. He has a set of the 3" wide F150 Deavers that we will be using for the rear. Chad is my cousin so it works out well.

Not sure If I'm going to go through the bed or keep it under the bed yet. The rear will never have more than about 16 inches of travel. The truck had a 28 spline 9 inch 5x 4 1/2 bolt pattern. I swapped in an 83 bronco 8.8 that I already had with 4.56s and a spool.

The truck was actually lowered when I got it. It has a C6 and I have installed some 3" blocks I had laying around to get the ride height close while I'm working on it. The 8.8 is longer than the 9 so I'm trying to figure out drive shaft length. The C6 is slip yoke and I don't plan on changing that. I'll run a strap around it to prevent destruction in case of joint failure or whatever.

I sold the 9 so I can't measure the difference in lengths (didn't think of it at the time) Here is my question, with the bump and droop experienced by the rear end will the stock shaft handle it? Should I have a new shaft built with a slip yoke or what?

Thanks in advance,

[DANNYV]

Currently i have an 8.8 in my bronco and want to swap it out with a 9''. I am going to the junk yard and want to know if any other truck would have a 9'' that will be a straight swap.

[damon1272]

Currently i have an 8.8 in my bronco and want to swap it out with a 9''. I am going to the junk yard and want to know if any other truck would have a 9'' that will be a straight swap.

Look for a 80-86 f-150 or bronco. These will have the rear ends that are a direct fit.for the 80-96 bronco

[philofab]

Currently i have an 8.8 in my bronco and want to swap it out with a 9''. I am going to the junk yard and want to know if any other truck would have a 9'' that will be a straight swap.

Look for a 80-86 f-150 or bronco. These will have the rear ends that are a direct fit.for the 80-96 bronco

Not all 83-86 1/2 tons had 9" rears. The 8.8 was an option in those years.

[PaulW]

Do the vans have 9". If so then the wider track would be nice for fat tires.
PaulW

[Phoenix0783]

Currently i have an 8.8 in my bronco and want to swap it out with a 9''. I am going to the junk yard and want to know if any other truck would have a 9'' that will be a straight swap.

Mine was out of a '79 Bronco, so Broncos and trucks of that vintage should work as well.

[ChaseTruck754]

Currently i have an 8.8 in my bronco and want to swap it out with a 9''. I am going to the junk yard and want to know if any other truck would have a 9'' that will be a straight swap.

Where you at? I've got a 9" out of a bronco sitting in the shop right now. It showed up as trade and I've got it for sale on DR for $275

And yes as Paul said the ones out of an econoline are wider. I think 1.5" wider overall (.75" per side) but Philo should be able to say for sure. I know it's not much extra width but look at your bedsides if you are doing this.

Also I believe the van ones are 28 spline whereas the bronco ones are 31 spline.