Rear axle replacement
- Thread starter Pmcb
- Start date
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59840Surfer
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- Joe
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- 1986
- Truck Model
- K5
- Engine Size
- 350 Stroker to 383 with a 400 crank, Crane Cam, Q-Jet, single 3.5" exhaust..
"IF" being the operative here --- it doesn't always work out that they've been changed - especially when it means two gear sets.
The RPO is still a good starting place.
100% of everything I've ever owned (7 K5s, 3 K1500 Sierras, 1 K40 box van, not counting a couple of Trail Blazers) have had the OE gears and NOT been changed.
100% trumps 90%.
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- 350-454
That's very true, it's still a good starting point. I've had somewhere around 60 cars and trucks, I can only recall 2.5 of them that had be re-geared. Only one of them was a surprise.
Frankenchevy
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The one that was 0.5 regeared would be interesting when shifted into 4wd…unless it was set up for mud racing.
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It was a '77 K5 that the rear 3.73 axle had been swapped out for a 3.08 axle. The PO found out about it the hard way, lol. He wasn't the best at diagnostics and replaced the trans and t-case before he figured out what was wrong.
Ricko1966
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Now go back to post 17 which is what I was talking about and quoting. At this point when you have the ring and pinion this close,to take pics that I can see the teeth. Why wouldn't you just count teeth?Why would I tell him to look up the RPO? No guess work there at all. Count the teeth it's 100 percent.
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AuroraGirl
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im sure theres a way to change your tire size to accomodate that... LOL.. imagine. the opposite of squatting before it was cool. Or would it be squatting?
59840Surfer
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- Truck Year
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- Truck Model
- K5
- Engine Size
- 350 Stroker to 383 with a 400 crank, Crane Cam, Q-Jet, single 3.5" exhaust..
If you have the cover off - the gear count is OEM-stamped into the outer periphery of the ring and on the inside stub of the pinion.
Most times, the number will appear like this ---> 33:6 or something like that.
These gears are machined together and have match-marks to keep someone from putting the wrong gears together and shipping them out as a pair.
I had the gear count on my old OE (3.08:1) gears and the same metric was stamped on the ring gear I got to replace them.
Funny enough --- GU4 is the same RPO code posted in my glovebox for 3.08:1 too!
Whatdoyouknowabouthtat?
