BE 12 bolt questions

**Fast67VelleN2O** · #1 02-22-2011, 10:07 PM

Is there a different part number (from a stock 4.10 gearset) stamped into the ring and pinion on a BE COPO 12 bolt gear set? If so, what is it?

Thanks,
-Matt

**Mr70** · #2 02-23-2011, 12:00 AM

The 4:10 ring & pinion gear part #3917971 is what Chevrolet used on the BE COPO.

**427king** · #3 02-23-2011, 12:33 AM

"Is there a different part number (from a stock 4.10 gearset) stamped into the ring and pinion on a BE COPO 12 bolt gear set? If so, what is it?".....................the standard ring and pinion in a 410 axle is #526 and #528, while the copo 410 gears are #226 and #228..

**ANDY M** · #4 02-23-2011, 03:35 PM

It should look like this:

**69 Post Sedan** · #5 02-23-2011, 03:55 PM

https://www.yenko.net/ubbthreads/ubbt...p;Number=20330

Per Ed Cunneen:

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">The part number for the 4.10 set was 3917971.
The ring and pinion part numbers are as follows:
3916226 Ring Gear 3916228 Pinion Gear
Case part number was 3916234 </div></div>

**Fast67VelleN2O** · #6 02-23-2011, 05:10 PM

Ok.... so it looks like I have a set of these gears that came with a 174 posi unit I bought back in October. They have been sitting on the shelf ever since. How do I tell if the posi unit is a COPO unit without taking it apart?

**Fast67VelleN2O** · #7 02-23-2011, 05:36 PM

Here are some photos of what I picked up.

**scuncio** · #8 02-23-2011, 06:01 PM

I think the correct side gears have no 'flange' on the sides facing the clutch plates. Hard to tell from your picture.

69L72RS · #9 02-23-2011, 06:12 PM

Matt,
That is a standard duty 4-series unit, based on the posted pictures.
Here is a #234 unit to compare.

**Alss** · #10 02-23-2011, 06:16 PM

How about the difference in the dates..5-69 and 1-70?..did the factory gears come in sets??..I have a standard 4 10 gear set in my COPO and both gears have the sama date..just curious and do not want to diminish the value of these gears..oh and by the way [img]<<GRAEMLIN_URL>>/Can-I-Have-It.gif[/img] [img]<<GRAEMLIN_URL>>/beers.gif[/img]

Albert