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4.63 on 19.5's

B

Brooklyn Tow

9 11 Never Forget
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Location
Brooklyn, NY USA
According to my RPO codes, GK9 = 4.63 rear axle ratio....

My question is, does that take into account my 19.5" wheels, or is the 4.63 standard across the board and the wheels gear me down?
 
The rear axle ratio is entirely unrelated to your wheel diameter. You have 4.63 times as many teeth on your ring gear as you do on your pinion, that's it.
 
It depends on overall tire height. If you currently have 31" tall tires on 19.5" rims and you switch to 31" tires on 16" rims, there will be no change.

HTH

Bill
 
I would guess with the HD lift, the 19.5 tires are larger than 16's stock, and have a heavier load weight. Thus they geared it up, everything helping GVW of 16,000 or whatnot that you have.

Since its a 2wd, changing the gear ratio to 4.10 wouldn't be all too much work, it would probably tone you down a little on the highway, but you'll obvoiusly lose low end torque.

How many RPM's you turning at 60?

With my 4.10's and my 31's (roughly ) 235/85 16, I'm turning 2k even.
 
NVW said:
Louis, that is about the same rpm's I turn at 60 mph with 225/75/16 tires. IIRC I'm 2200 at 60

Leo
Click to expand...

Yep, same here when I had those tires... GM must have thought that was an optimal final drive ratio. Must have went 19.5's to handle weight. FWIW, I love 60 at 2k. It just feels right to me.
 
Brooklyn Tow said:
Don't know inches...Tire size is 225/70/19.5
Click to expand...


those tires are about the same size as 235/85 16's. Slightly larger (100" circumference vs 99) So call them the same size. If those are stock, then GM just bumped the gear ratio up to keep the 'ideal' final drive ratio. Those are probably the smallest (or close to it) 19.5's you can get I would guess.
 
Matt Bachand said:
those tires are about the same size as 235/85 16's. Slightly larger (100" circumference vs 99) So call them the same size. If those are stock, then GM just bumped the gear ratio up to keep the 'ideal' final drive ratio. Those are probably the smallest (or close to it) 19.5's you can get I would guess.
Click to expand...



You hit the :hammer:


How'd you find those numbers Matt? I guess that makes it official....
Another 6.5 mystery solved. :thumbsup:
 
Brooklyn Tow said:
That is one Nifty Grill you got there Leo......Did you build that bad boy? How many T-Bones can you fit on there?
She's a beaut!
I've never seen a barbecue with a trailer reciever!
Click to expand...

I built it for a neighbor for pig roasts and big bashes, it's still a virgin. the cooking area is 3'x6', wood, charcoal or lpg. It was a project I did in my spare time, a lot of hours went into it's planning and construction, I drilled over 2000 holes for the burners. ie: didn't pay very well.:mad2:But I'm pleased with it:D

Leo
 
Looks like you could fit a baby elephant on there.....
I bet it cooks as good as it looks......(2000 holes)...Your a good friend.
I'm a charcoal man myself.....from when I was a kid, gas (propane) wasn't very popular....

When's the party?
 
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