Stink Ten Two. The second Blazer.

[HO455]

The pinon seal started leaking. At first I noticed spots the size of a half dollar but they quickly got more significant. So I decided if I was going to have to deal with the seal I would change the gear ratio too. The F-body T56's have a 2.66 first gear ratio which I'm sure GM chose due to fuel and emission concerns but otherwise they're a real buzz kill. Especially in stop and go traffic combined with 3.42 rear gears.

The truck had 3.42's in it when I got it. There was a receipt for them being installed along with a list of new parts in the documentation that came with the truck. I wanted to put a set of 3.90's in but they were back ordered so the next best option for me was 3.73's. I ordered a set along with a pinion spacer set to be used instead of a crush sleeve. Then I dropped the truck and parts off at Six States and had them install the parts.

I am pleased with the results as the truck is nicer to drive in traffic with less need to slip the clutch when starting out. On the other end now 6th gear is usable at 60 mph instead of 65. I still think 3.90's would have been the best compromise but I'd probably still be waiting for them to come off back order and leaving a trail of gear oil everywhere I went.

As a side note the shop reported that the reason the pinion seal was leaking was the pinion shaft bearings were loose and the carrier wasn't shimmed properly and it had slightly too much play. So a new set of bearings got installed too. Now the truck certainly seems smoother at this point.