I am going to do a final drive ratio gear change to 4.10 and have been reading up on the two suppliers and results that others have had.
Quite a few comments on various forums about the Nitro gears being noisy, but also comments that it is all in proper setup not the fault of the ring and pinion quality.
I ended up ordering both Nitro and Spicer (labeled made in USA) ring and pinion sets.
Visually they both look very good as far as tooth finish, etc (of course visual does not tell you anything about actual heat treat and strength or fabrication tolerances)
The Spicer part number 2017552 is the 4.10 ratio for the "M190" Front Differential (apparently requires ring gear spacer)
The Spicer part number 10004299 is the 4.10 ratio for the "M220" Rear Differential
The Nitro part number is D32-410T-NG for the "Dana 32" Front Differential (this new design is thicker and does not require ring gear spacer)
The Nitro part number is D46-410-NG for the "Dana 46" Rear differential
So the odd thing and reason for title is that the tooth (pitch) angle is very different between the Nitro and Spicer (see photo). From what I can find this theoretically has no effect on efficiency or strength, but does affect bearing thrust under power. I am wondering if this could also affect potential for gear noise.
SPICER RING GEAR ON LEFT NITRO RING GEAR ON RIGHT
Quite a few comments on various forums about the Nitro gears being noisy, but also comments that it is all in proper setup not the fault of the ring and pinion quality.
I ended up ordering both Nitro and Spicer (labeled made in USA) ring and pinion sets.
Visually they both look very good as far as tooth finish, etc (of course visual does not tell you anything about actual heat treat and strength or fabrication tolerances)
The Spicer part number 2017552 is the 4.10 ratio for the "M190" Front Differential (apparently requires ring gear spacer)
The Spicer part number 10004299 is the 4.10 ratio for the "M220" Rear Differential
The Nitro part number is D32-410T-NG for the "Dana 32" Front Differential (this new design is thicker and does not require ring gear spacer)
The Nitro part number is D46-410-NG for the "Dana 46" Rear differential
So the odd thing and reason for title is that the tooth (pitch) angle is very different between the Nitro and Spicer (see photo). From what I can find this theoretically has no effect on efficiency or strength, but does affect bearing thrust under power. I am wondering if this could also affect potential for gear noise.
SPICER RING GEAR ON LEFT NITRO RING GEAR ON RIGHT