Dealer tells me that these parts are discontinued and can not be ordered. I want to swap the rear gears in my '96 Roadmaster from stock 2.45 ratio to something like a 3.70 or maybe a 3.90, using a brand that will accept the stock anti-lock brake reluctor (the thing that slips over the pinion shaft, has metal teeth on one end). I will need the right matching reluctor for the anti-lock brake circuit. Anyone have any idea where I can get the one that will work with a 3.70 or 3.90 ration ring and pinion? FYI... this is a Roadmaster so it has the 'corporate rearend'.

 

Found my own answer... here it is to help if you or anyone else may need it. GM part no.s are
26018944 for 3.23 ratio & reluctor has 22 teeth
26018945 for 3.42 ratio & reluctor has 20 teeth
26018946 for 3.70 ratio & reluctor has 18 teeth
26018947 for 4.10 ratio & reluctor has 16 teeth

Order from www.drivetrainspecialists.com
pick the reluctor closest to the ratio gears you are changing to