• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

3.42 Gear Ratio vs. 4.10

MrOutdoorsie

Full Member
Joined
Nov 22, 2005
Messages
16
Location
Colorado Springs, CO
I'm trying to decide what gear ratio to go with for my new '05 or '06 AV.  I don't do any trailering, really, and don't plan to any time soon.  Most I'd do is hauling a motorcycle or two in the back or some big Home Depot runs.  But I do live in Colorado, and I drive in the mountains quite often.
I'm more concerned about gas mileage than towing capacity.  Does anyone know the difference (if there is any) between the 3.42 rear end, and the 4.10, gas mileage wise?
Thanks!
 
You pretty much know the answer I think.  I tow a camper trailer, around 3500 lbs. and have no problem.  I believe mine are 3.73 though.  But if it is gas mileage you seek, go for the 3.42s.  Also see what the difference in towing is, I'm sure the 3.42s will tow what you need.  Your new truck will have more than enough power to go up the mountains.  And if you disagree, just mod like the rest of us.  We'll help  >:D
 
I like my 4.56's  :D


Gas milage: 15mpg if you baby it. 
Towing capicity: unknow, but great

Stepping on the gas and it doesn't feel like your in a 6000# truck: priceless  >:D

 
I'd go with the 4.,10's,  the altitude robs the engine of HP, approx 7-10 loss, to make up for it go with the 4:10's, you'll be glad you did, with all the hills in the Denver area you'll be downshifting out of overdrive all the time just to accelerate on the hwy with the 3.42's
 
KY_BOB said:
I like my 4.56's  :D

Gas milage: 15mpg if you baby it. 

You're kidding, right?  15 with 4.56 gears?  Downhill all the time? :laugh:  jk-Mine never saw 15.

4.11's would be much better in CO with the hills. You would have to mash the gas lots more to get it going with the 3.42's.

 
I guess it also depends on how much modding you plan to do.  I have done just about every power mod except a blower and will take hills like crazy with my 3.73's.  No downshift, but that is aided by my custom tune.  So look into how many mods you plant to do, multiply that number by 3, and consider that in your decision. 
 
nfhjr said:
If 3.73 is available go for them
??? ???

3.42 replaced 3.73 for '05+

Still just two options, now 3.42 or 4.10.
 
My 4.10 just gave me a 16.78 time at 81.92 mph in the 1/4 mile at Bithlow.  Respectable I think for a completely stock AV with 7500 miles. :cool:
 
I ordered my '06 with 4.10 gears and am pleased.  A few steep hills here in town and the beast crawls up with very little effort.
I don't know how accurate the DIC MPG estimator is, but I've gotten a steady 18 MPG on the freeway at 65-70 MPH.  Really bad though in town, in traffic...like, 11 MPG.
I haven't driven and AV with 3.42s, but my 4.10s are GREAT in stop-and-go traffic, too.
 
Thanks for the replies, everyone.  This thread, plus some on the Towing/Hauling threads have pretty much convinced me to go w/ the 4.10's.  After all, I'm not buying this thing for it's fuel economy.  But every little bit helps, ya know?

But now I have another question.  Would the Z71 package, with it's 17" wheels necessarilly get better or worse fuel economy than one of it's simarly equiped 16" wheeled cousins?
 
MrOutdoorsie said:
Thanks for the replies, everyone. This thread, plus some on the Towing/Hauling threads have pretty much convinced me to go w/ the 4.10's. After all, I'm not buying this thing for it's fuel economy. But every little bit helps, ya know?

But now I have another question. Would the Z71 package, with it's 17" wheels necessarilly get better or worse fuel economy than one of it's simarly equiped 16" wheeled cousins?

Equipped otherwise identically (4x4, same gears), the mileage really won't differ.  The rolling height of the two wheel/tire combos is fairly close.
 
Back
Top