[beetle9]

I'm trying to think of everything before it happens here and this may be a silly question, but I'll ask anyway. I just had a ford 9" narrowed for my old 35 ford and noticed these rear ends have an "off centered yoke" (laterally). It is offset to the passenger side a couple inches. I know the vertical angle is important and should be consistent with the driveshaft and the tranny, but what about laterally. The yoke on the rear will not be in the center. Is this a problem and do I need to compensate in some way?

[PAULWELDIT]

If you are building a race car this maybe be a concern and mainly from the standpoint of power loss. Most street rods it's not a concern as many factory car suspensions were like that. I think your looking at an off-set of 1 1/4"which is probably not a problem but you do need to check it on your car because the driveshaft tunnel in the floor on early Fords is very small.I just finished a '36 Ford Roadster with air bags--the pinion had to be centered on it because the customer plans to drive the car "On the Ground"
Paulweldit

[beetle9]

Thanks for your reply. I'm glad it's not a major problem, don't need any more obstacles, it's tough enough just dealing with all the routine snags when building a rod.

[dmorris1200]

If you notice the member is not centered in the housing, that's why the axles are different lengths. But the pinion/yoke is not centered in the third member either to offset this. Since the yoke sits off to the side of the third member the distance from the yoke to backing plates should be almost the same. Basically the yoke is centered but the third member itself isn't. I haven't measured mine to the inch but peaked under the car and looked and the driveshaft to the naked eye looks centered even though the member is not centered in the rear.

[ May 13, 2002: Message edited by: dmorris1200 ]</p>

[gcomer3]

You should have no problems with a centered housing. When I narrowed my 9" for my T Bucket, I centered the housing because you see it from the back. A lot of street rods go ahead and center the housing when they have it narrowed anyway. I have never heard of a problem with the drive shaft being off center laterally.

[57Chevyman]

The only problem you may encounter is that on an open rear end the shorter axle can spin first because it often poses less resistance to the spyder gears. This is no real concer unless the car is being raced and in that case you would use a posi or solid spool.

[dmorris1200]

I've had an open differential in mine for 11 years and never found it to react differently than any other rear with equal length axles. If I'm making a right and punch it right tire smokes, if making a left and punch it left tire smokes. Heading straight from a stop right tire usually smokes like most other cars and that's the longer axle.

[beetle9]

Not too concerned about the axle length issue, just vibration issues. If vertical pinion angle is such a big issue, why is horizontal pinion angle not as important? I have double checked and the actual housing is centered, but the yoke is offset almost 2". I know that u'joints are designed to compensate for two mis-aligned shafts that have been joined, but how much is two much?

[dmorris1200]

If people shortened these rears the way Ford intended for them to be (with one axle longer than the other) the yokes would all be centered and you wouldn't have these questions. If you're concerned with the housing being centered from behind use a G.M. rear. Why butcher a Ford one.

[ctb460]

I have the same issue with my 9 inch rear I just bought. The pinion is off set 2-3 inches. The housing seems to be centered though? I just got it and when I laid it in place I got very confused. I uderstand that one axle should be longer than the other, but if I measure the distance from the brake backing plate to the frame and even it out, the pinion should be in the middle, right? Mine is definetly off to the pass. side. Why would a factory set up the driveshaft off center, instead of moving the housing over to center the yoke? Do they have center sections that have the pinion centered, or are all 9's the same? I'd prefer to have the housing centered, as well as the pinion. The driveshaft can't be off set - No room! I'm more confused about why it is, than what to do!

[SJFast]

That offset is a result of the basic 9" Ford rearend design. If you want the pinion in the center you must have different length axles (right side being the longer of the two). Conversely, if you want same length axles, you'll end up with an offset pinion. There's no way around that !

The offset pinion would not be a problem if the driveshaft is long enough (so that the recoomended U-joint angles aren't exceeded) or if there's a clearance problem with the floor tunnel as in a lowrider. On a short wheelbase car with engine setback (like a T-bucket) I'd have the pinion centered.

[dmorris1200]

If the housing is centered someone already modified the rear or probably shortened it and made the axles equal length. As stated the axles need to be long/short with the center section (third member) offset to center the pinion.

[ctb460]

This forum is a great place to come for answers! A lot of mine were answered just by reading through all the question, the others I got plenty of great responses to. Thank You.