Help with banjo rear
 

I pulled the banjo out of my roadster. I drove it once and noticed some pretty loud howel on deceleration.
What I know
I think it’s a 40’
-The gearing has matched etching from ford that says 3.57 (I counted the teeth and it’s 3.54) the gear faces look really nice.
- the spiders seem tight and everything spins as it should.
- the preload seems to be off on the pinion. I have about 1/16” play at the bearings (allowing the pinion to walk in and out of the housing) some lateral movement too due to lack of preload.
-I have about 3/8” movement. The entire carrier and axles can slide in and out towards and away from the pinion. Obviously the wrong bearings/ races and or wrong carrier?
-the bearings in the carrier appear used but decent and the races look good as well. The carrier can move so far over to the left (drivers side) that I can see where the ring gear rubbed in the webbing of the bell.

Thoughts?

Re: Help with banjo rear
 

I use only Timken bearings and cups. I've had some big problems with cheap bearings. The carrier bearings should have a stiff drag on them,no side to side movement. A .010 gasket on each side of the banjo will get you in the ball park. On the pinion using new bearings and double cup I tighten the preload so that when I clamp the pinion in the vise and spin the banjo with both hands it will make only one turn.

Re: Help with banjo rear
 

If you need a measurement for the carrier I have three I can measure. The gaskets thickness on the axle housing to the banjo center section adjust the ring to pinion lash but the carrier shouldn't move side to side once the axle housing is bolted together. Sounds like someone didn't preload the pinion right or didn't bend the lock washers over the nut and it came loose.

Re: Help with banjo rear
 

I’m guessing that someone installed incorrect bearings on the carrier... does anyone have dimensions of the correct bearing sizes? I can try to measure what I have before I but new

Re: Help with banjo rear
 

Pinion bearing races # 27820D
Pinion bearings # 27880
Diff bearing races # 25522
Diff bearings # 27880
Pinion pilot bearing # that I have is a Federal Mogul # R–1304–BF

Don't have the dimensions of the bearings but here are the numbers for them

Re: Help with banjo rear
 

Loss of preload always causes a howl on deceleration. They have to be set up with no shake and a preload.

Re: Help with banjo rear
 

The adjustment procedure is in Ford Service Bulletins along with Spec. Determine what year your looking at first.

Re: Help with banjo rear
 

I guess Timken bearings are ok but like many others, they too are all made in China now so you really can't be sure. Timken production moved there several years ago.

Re: Help with banjo rear
 

I’ve been studying the rebuild guide and some website references and have a pretty general idea. I get the shimming on the bells to change the preload. The issue with mine is less of the minute adjustment of shimming / gaskets at the bells. The entire carrier and axles move 3/8” into and away from the pinion. I can see where the back of the ring gear has worn the webbing on the bells

Re: Help with banjo rear
 

Adjusting the shims on each side of the center section is not related to preload. The pinion preload is set by adjusting the nut on the front of the pinion. The shims adjust the backlash between the pinion and ring gear.

Re: Help with banjo rear
 

Yes. Sorry, backlash not preload

Re: Help with banjo rear
 

3/8" ????? I think you will need to replace everything in that rear. The loose metal has damaged everything. Aparently the only thing centering the axles are the hubs riding on the ends of the axle bell stubs.

Re: Help with banjo rear
 

I have photos but I can’t seem to get them loaded from my mobile device. My guess is that it was slapped together but not ran.... like I said I drove it once (didn’t notice the side to side play beforehand) before I pulled it and took it apart. Suppressing how everything inside looks good. Gears look really nice. I may be lucky that nothing was damaged. I’m out of town on vacation so I can check the carrier bearing sizes posted above. But my guess is that someone installed the wrong bearings and or races.

Re: Help with banjo rear
 

I pulled the bearings from the carrier and the races from the bells. It turns out that the carrier bearings are early banjo 18-4221 original ford stamped. The races are new bearing size. The part number on the race is timken 25522. Obviously a mis-match.

Here is what I know now.
I have a v8 center housing (3-13/16” wide)
10 spline pinion
3.54 gears (original ford stamped and in great shape.
4 gear spider
18 tooth axles 32-3/4” overall length
Bells I believe are 1940. The machined area to accept the races is .7535” deep
The depth of the machined area on the carrier to accept the bearing is .90” deep and has a dia of 1.689 on both sides. No evidence to prove that a bearing has ever “spun” on the carrier so that’s good news.
The carrier has a cast number of 4206


The million dollar question is..... what carrier bearings do I buy? Early or late?

Re: Help with banjo rear
 

39-41 axles 32.85"-16 teeth use 11 tooth spiders

35-38 axles 32.85"-18 teeth use 12 tooth spiders
It was 37 when the bearings changed from early to late.

look on line to see the Timken bearing and race dimensions, there may be a difference in race OD ???

The early Timken combination 22168 & 22325
the late is 25578 & 25522

Re: Help with banjo rear
 

That's not totally true. Preload setting is required for carrier bearings as well as pinion bearings. The gaskets/shims set preload on carrier bearings first, then by adusting previously established shim thickness side to side you set ring and pinion gear backlash.

Re: Help with banjo rear
 

Very true! I guess I gave too short a version. :)

Re: Help with banjo rear
 

If the new style race 25522 fits in the axle housing, 3.27" OD, you need the new style bearing 25578. The old style race is 3.25" OD.
See www.bdiexpress.com for the Spec.