AAM 3.91 Ring Gear PN Quick Question - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

nate1590 · 01-29-2026, 08:48 PM

Just purchased an American Axle 3.91 ring and pinion to replace my 3.45 factory gearset. My question is should there be a part number etched/stamped into the outer rim of the ring gear? The pinion has a 4 digit pn and 11x43 forged into the end, but the ring doesn't have identification, and I want to ensure it is the correct ring and also genuine aam. Anyone remember what theirs had stamped/etched?

Joe.G · 02-02-2026, 07:33 AM

If I remember correctly Mine was etched on both, 11 X 43 would be correct, Count the ring it should have 43 Teeth. Are they used? Not in original package? buy it from a private seller or non reputable shop?

nate1590 · 02-02-2026, 09:09 PM

It was a reputable gear shop in the midwest, good reviews and spoke with the gentleman prior to purchasing. I asked him, and he said its common to not see them marked. Both teeth counts are correct. I'm going to not worry about it and install. They were in the AAM box for the correct P/N but had been unwrapped prior, definitely not used though.

01-29-2026, 08:48 PM	#1
nate1590 Drives: 2010 Camaro 2SS/RS Join Date: Jan 2026 Location: RI Posts: 2	AAM 3.91 Ring Gear PN Quick Question Just purchased an American Axle 3.91 ring and pinion to replace my 3.45 factory gearset. My question is should there be a part number etched/stamped into the outer rim of the ring gear? The pinion has a 4 digit pn and 11x43 forged into the end, but the ring doesn't have identification, and I want to ensure it is the correct ring and also genuine aam. Anyone remember what theirs had stamped/etched?

02-02-2026, 07:33 AM	#2
Joe.G Drives: 2014 2SS/RS 6SP Ashen Grey Join Date: Aug 2021 Location: NY Posts: 1,775	If I remember correctly Mine was etched on both, 11 X 43 would be correct, Count the ring it should have 43 Teeth. Are they used? Not in original package? buy it from a private seller or non reputable shop? __________________ GM 3.91/TrueTrac OEM ZL1 Rims, 6 Piston Brakes & Side Skirts.ACST4 Splitter/Deflectors NPP M2W,GM Short Throw,GPI Ported Rod Mod,BO White PTB,CAI/JRE Scoop, GC Aluminum DS,Stainless Works Ceramic LTH/HiFlo Cats, Hotckis 1" Springs & Chassis Max Brace BMR Adjustable Swaybars,Trailing Arms, Adjustable Toe Rod, LCA & Z28 UCA Bushings Hendrix Solid Cradle Bushings Pedders Radius Rod Inserts Strut tower brace, Moroso Catch Can,SCT X4 Dynosteve,Remote Clutch reservoir,Hero Smoked Tail and 3rd Brake Light, Diode Dynamic SL1 Fog Lights AeroForce Dual gauge/Autometer pillar mount.

02-02-2026, 09:09 PM	#3
nate1590 Drives: 2010 Camaro 2SS/RS Join Date: Jan 2026 Location: RI Posts: 2	It was a reputable gear shop in the midwest, good reviews and spoke with the gentleman prior to purchasing. I asked him, and he said its common to not see them marked. Both teeth counts are correct. I'm going to not worry about it and install. They were in the AAM box for the correct P/N but had been unwrapped prior, definitely not used though.