Ford 9 inch carrier bearings and such

[br0nc0xrapt0r]

So I am putting together some 9 inch diffs for a customer and things have gone awry.

I should have just ordered parts myself but he had already bought them, He got strange nodular cases and he wanted 31 spline front and 35 spline rear, I would have just stuck to one for both but whatever. He then ordered bearing install kits with 3.06 carrier bearings. They will fit the 31 spline with a 1.78 journal but both cases are 3.25 bearing size.

This is an easy fix for the 35 spline diff, just get 3.25 bearings. But what to do about the 31 spline?

I need a bearing that fits the 1.78 journal and fits in the 3.25 case. Does such a bearing exist? If this guy needs a different case or locker he's going to be pissed but oh well, I am not the one that ordered it...

It's late here so I won't be able to call Currie or just diffs until later but if anyone has some insight that would be great. Lesson learned next time someone wants diffs built I'm ordering all the parts.

 

[bronconut73]

So I am putting together some 9 inch diffs for a customer and things have gone awry.

I should have just ordered parts myself but he had already bought them, He got strange nodular cases and he wanted 31 spline front and 35 spline rear, I would have just stuck to one for both but whatever. He then ordered bearing install kits with 3.06 carrier bearings. They will fit the 31 spline with a 1.78 journal but both cases are 3.25 bearing size.

This is an easy fix for the 35 spline diff, just get 3.25 bearings. But what to do about the 31 spline?

I need a bearing that fits the 1.78 journal and fits in the 3.25 case. Does such a bearing exist? If this guy needs a different case or locker he's going to be pissed but oh well, I am not the one that ordered it...

It's late here so I won't be able to call Currie or just diffs until later but if anyone has some insight that would be great. Lesson learned next time someone wants diffs built I'm ordering all the parts.

It must. I have the 3.25 diff bearing housing (Strange Case) and I have 31 spline WH axles.
Got my bearings there.

 

[br0nc0xrapt0r]

It must. I have the 3.25 diff bearing housing (Strange Case) and I have 31 spline WH axles.
Got my bearings there.

That's reassuring, I just love telling him that the parts he bought won't work. Last thing I wanted to tell him is that the big money case won't fit.

Still iffy though as I cannot find 1.780 to 3.250 bearings...

 

[bronconut73]

That's reassuring, I just love telling him that the parts he bought won't work. Last thing I wanted to tell him is that the big money case won't fit.

Still iffy though as I cannot find 1.780 to 3.250 bearings...

Hmmmm.....
Nine Inch Nodular on eBay and WH are the only two places I went to get stuff for the nine inch.
Keep us posted....wish I could find some part number reference for ya' on my old paperwork....

 

[br0nc0xrapt0r]

At the same time I don't see any 31 spline carriers that have a 2 inch journal. I'm thinking it's the bearing, like when I ran big bearing shafts in my old small bearing housing. You don't see it out there but it's there, I hope.

I'm willing to go the extra mile to make this work for the guy but in the end I didn't order the parts.

 

[Apogee]

Conversion bearings are out there, so no worries.

http://www.quickperformance.com/Ford-9-Carrier-Bearing-Race-Conversion-1781-ID-3250-OD_p_20375.html

Given the bearings, there's almost no reason not to run the 3.25" case now...I wish I had gone that way for future upgrade options, but I didn't know about the bearings.

 

[Yeller]

ECGS will have what you need on the shelf and know exactly what you need if you call them.

 

[welndmn]

WH sells a conversion race to fit the 31 spline bearings in the 3.25 cases.

 

[DirtDonk]

Guess I need some edification.
Why is there even a need to match the axle shaft, when we're talking about the inner carrier bearings? We don't change bearings when installing a 31 spline axle into an originally 28 spline case. Why would we need to do it for 35's?

I understand that a 35 won't fit a stock smaller carrier bearing because it's too large to fit through the bore, but with any larger 3.25 bearing in a nodular case, all axles should slip right through to the splined gears. Right?
Otherwise, it sounds like you would not be able to install a 28 spline diff and axle into a large bearing nodular case without some sort of conversion/adapter bearing assembly too.

So why are we trying to match the bore to the axle shaft, when it's not a part of the supporting components. I always thought (perhaps erroneously) that the only two supports that the axle shafts got were the outer "wheel" bearings and the inner splined side gears.

Is that not the case?

Thanks for any enlightenment.

Paul

 

[Apogee]

I think that the issue is finding a differential/LS/locker that is sized for the smaller axle spline count and larger 3.250 bearings. They don't exist, so you must find a bearing with the 3.250 OD and smaller 1.781" ID to work.

Just for reference, the common Ford 9" carrier bearing sizes are as follows:

2.890 OD x 1.781 ID
3.062 OD x 1.781 ID
3.250 OD x 1.781 ID
3.250 OD x 2.000 ID (35-spline applications)

While you can run 35-spline spools in the smaller bearings, they're generally not preferred, and I don't know of any other carrier/locker types that allow you to do that.

 

[DirtDonk]

Ahhh, he says, with the light coming on. Thanks for that. I was thinking you all were talking about the axle shaft fitment, not the carrier itself.

Thanks again.

Paul

 

[br0nc0xrapt0r]

Got everything ordered from ECGS after I was able to confirm with the customer what yoke size he wanted to run.

 

[br0nc0xrapt0r]

I'm going to give ECGS a chance to fix this but I'm a little more than pissed right now. I got the conversion bearing alright but they sent the wrong bearing for the other big case and 35spline carrier. They sent a regular 1.78x2.89 bearing for the other. They also sent the yokes separately, and did not tell me they were doing this, nor did they give me a tracking number for them. The first clue should have been when the sales person kept cutting me off with "I know" when I was telling him the sizes for the bearings. I'm sick of telling the customer it's going to take longer. Yes the first boo boo was his mistake on the install kits but this is getting to be a saga now.

I want the damn yokes and proper bearings overnight. When I'm in my shop reading you numbers off a set of calipers that's your clue to listen.

 

[edgeoffroad04]

Digging up an old thread here, but can anyone tell me what size carrier bearings were used on the Classic Bronco's ford 9 inch? I.E. based on a small bearing vs. medium vs. Large large bearing axles...hopefully this is easy and the same carrier bearing was used through out the entire run for the Classic Bronco for each axle...Thanks!

 

[DirtDonk]

Good question. Hopefully someone has a definitive answer after all these years. I thought I'd seen multiple sizes crop up over the years, but who knows if they were even the original 3rd members people were pulling out of their Broncos.

Look forward to learning which is it as well.

Paul

 

[Apogee]

As far as I know, both the Ø2.890 and Ø3.062 bearings were used in EB applications, so without pulling and checking the case, I don't know of any way to tell what it is based on year/make/model, VIN, axle GVW rating, etc. Even if there is a way to tell, I'd be hesitant to trust it given the age of these rigs and number of times most have been around the block.

 

[edgeoffroad04]

Apogee thanks for the response. It looks like I just need to go and measure my own bearings to confirm size. Ill pass along my #s once I do this.

Does anyone have a preferred brand of bearings to go with and where do you normally buy from?
Thanks!

As far as I know, both the Ø2.890 and Ø3.062 bearings were used in EB applications, so without pulling and checking the case, I don't know of any way to tell what it is based on year/make/model, VIN, axle GVW rating, etc. Even if there is a way to tell, I'd be hesitant to trust it given the age of these rigs and number of times most have been around the block.

 

[Timmy390]

I found this......It's a good read....just posting for information....It mentions Bronco's specifically
http://www.kevinstang.com/Ninecase.htm

The most popular rear end around is no doubt the Ford 9 inch unit, it is used by restorers, street rodders and racers alike, regardless of what brand of car the axle is going in. Many custom made axle housings for the GM boys utilize the 9 inch Ford, even though they hate to admit it. Ford used the axle from around the 1957 model year right up until the early 1980’s in cars and trucks. It was not the only axle used, but was by far one of the best. Variations by Ford exist in the size of the outer axle bearings in the housings and carriers both, as well as with the spline count on the axle shafts. Generally most cars received the small axle bearings and 28 spline axle shafts. Exceptions to this were the ultra Hi performance Boss 302’s, Boss 429’s, 427’s, 428 CJ/SCJ and the 429 cars which received the 31 spline carriers and axle shafts. Some of the heavier cars like the Galaxies,later Tbirds and mid 70's Torinos also received the larger wheel bearing housings.The trucks varied more, early half ton trucks got the 28 spline axles and carriers, while sometime in the early 70’s the switch was made to mostly 31 spline axles and carriers for trucks while some vans remained 28 spline. Most of the later trucks also received the larger axle bearings housings.One exception to this was the Bronco’s from 1966 to 1977, they stayed with the 28 spline units and in mainly small bearing housings, although some of the later 74-77 it seems started getting the heavier axle housing with large bearings. A small bearing housing can be differentiated from a large bearing housing by the size of the nuts and thread used to retain the brake backing plates to the housing, the small bearing housings use 9/16 socket size nuts with 3/8” fine thread, while the larger bearing use 3/4” socket size and 1/2” fine thread. Gross Vehicle Weight ( GVW ) would determine which axle housing many cars and trucks received.

Tim

 

[DirtDonk]

Does anyone have a preferred brand of bearings to go with and where do you normally buy from?

I think it still mostly comes down to most people acknowledging that Timkin is the go-to bearing.
They've been an O.E. supplier from almost the beginning and have kept their reputation for high-quality until today. For the most part...
They're no longer a majority "made in USA" product, but they're made in so many countries that they're not even thought of as "cheap imported crap" yet.
Countries like the US and Canada, Belgium and Germany, England and likely Japan and 5 or 10 other countries. When stocking shelves with them one time, to pass the time we tried to count all the countries-of-origin printed on the boxes. I think we were at 15 when we got tired of the game!

That's not to say that some of the other well known companies such as BCA and others you might know are not still good too though. I've had great luck with BCA, SKF, NTN and others, but I'm drawing a blank on their names at the moment.

I've personally never had a bearing failure with any company, but I still buy Timkin when I can, and that's what we sell at WH almost exclusively.

Paul