Two different spindels on the back of my 77 PB

RF_Burns

RF_Burns

Super Moderator
Staff member
Sep 7, 2008
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Ontario Canada
So I have the rear hubs off to do the rear bearings. When cleaning up the retaining nuts I noticed the ones from the drivers side are larger than the
passenger side. I measured the spindle size where the bearings go and they are the same 1.03" and 1.63" approx. on all 4.

The thread size diameter measures 0.73" on the passenger side and 0.84 on the driver's side. Obviously the spindles on one side have been changed at
some point. Bearing size seems the same.

Can anyone shed some light on the two different sizes?

Thanks

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
Sounds like a trip through the parts book would be in order. I know that
the bogie pins changed from one size to another around 1975 model year, and
bouncing around in my cranial cavity (void) there seems to be a memory of a
recall on the spindles about the time of the hydraulic drum brake upgrade
to self adjusters. But like I said, memory being what it is........
Jim Hupy
Salem, Or
78 GMC Royale 403

> So I have the rear hubs off to do the rear bearings. When cleaning up the
> retaining nuts I noticed the ones from the drivers side are larger than the
> passenger side. I measured the spindle size where the bearings go and
> they are the same 1.03" and 1.63" approx. on all 4.
>
> The thread size diameter measures 0.73" on the passenger side and 0.84 on
> the driver's side. Obviously the spindles on one side have been changed at
> some point. Bearing size seems the same.
>
> Can anyone shed some light on the two different sizes?
>
> Thanks
>
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Jim I recall the bogie pin recall. I had the bogie pins replaced but nothing was said about them being different from side to side. I guess the wheels
haven't fallen off in the 10 years I've had it. Lol
--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
So now I have noted the spindle washer is the same on both sides, so on the passenger side the washer is loose fitting on the spindle threads. I can
find Dorman 3/4" holed spindle washers, but none 2.25" OD. Most are about 1.75".

Should I stay with the existing 7/8" washer on a 3/4" spindle but with the larger OD, or go with a smaller OD but fits the 3/4" spindle?

What say yea?

Thanks

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
Bruce, I would think that the diameter of the threaded portion of the
spindle should match the washer. Because the washer tang indexes with the
slot in the spindle, you wouldn't want very much play there.
Jim Hupy

> So now I have noted the spindle washer is the same on both sides, so on
> the passenger side the washer is loose fitting on the spindle threads. I
> can
> find Dorman 3/4" holed spindle washers, but none 2.25" OD. Most are about
> 1.75".
>
> Should I stay with the existing 7/8" washer on a 3/4" spindle but with the
> larger OD, or go with a smaller OD but fits the 3/4" spindle?
>
> What say yea?
>
> Thanks
>
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Thanks Jim,
I found Dorman 618-032 is the closest ID and the largest OD at 44mm, but the OEM is 57mm. No place in Canada has them so might be a few weeks. I
figure the old one has been there for a long time, so hopefully it will last a bit longer.

GMCMI cross-reference is for the larger 7/8" spindle and has an even smaller OD and no index tab at all!

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
I located a recall campain from May/74 for '73 and '74 motorhomes to replace the spindle and hub. This was to install larger bearings. But the bearing
surfaces on both sizes of spindles are the same in my case. Only the thread for the retaining nut is different from side to side. 3/4" vs 7/8"

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
I have recall of that, but was unsure of the details. Your message stirred
that up a bit. I don't exactly remember the minute specs. I thought the
bearing diameters were different, but you have direct evidence to the
contrary. If the spindles are in good condition, and the drums and seals
are good, I would be inclined to use them until they are not.
Jim Hupy

> I located a recall campain from May/74 for '73 and '74 motorhomes to
> replace the spindle and hub. This was to install larger bearings. But the
> bearing
> surfaces on both sizes of spindles are the same in my case. Only the
> thread for the retaining nut is different from side to side. 3/4" vs 7/8"
>
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
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