98 3500 HD tow truck rear end help

I need work on the rear end seems the pinion gear teeth are gone. Would it be ok to just replace the pinion gear? or replace the ring gear also. The ring gear and all other parts look ok just the pinion teeth are gone. What would you do if it was your truck? I was going to replace the pinion and nut also the bearing and seal for the pinion. any good places to get pinion and ring gear. Need kinda fast. Live here in Boston area. Going to call dealer tomorrow morning.

Thanks

IIWMM (if it were my money :)) I would replace the ring and pinion as a set...if there's any contact issues with the old ring I think it will be magnified.

It would also be a good time to try to understand the failure mode...lube level got low or improper lube was used (??)

The 3500HD might use a different (heavier) axle all together from the typical GM 14 bolt "1 ton" axle...seems like Rockwell axles were used on the 3500HD IIRC as they had truck overall GVWs from 12000-15000 lbs.

You cannot even buy just the ring and/or pinion, they come in matched sets only.

Synthetic gear lube will do damage to the ring and pinion.I know of 3 rear ends going out due to synthetic gear lube.Problem with synthetic gear lube is that it is too hard on gears and this is true.I know some that replaced ping and pinions due to synthetic gear lube,my father's friend Rich.One was very noisey after someone put in synthetic gear lube and it was fine before it was done.There was nothing left on the ring and pinion gear gears,size of a pencil tip.