That chart is WAY off. My truck with 3.73 and 35s turns about 1800 rpms at 70 mph in overdrive.

With 4.56 gears it would be around 2150. with 4.88 gears it would be around 2350.

 

Sorry to comment this but if you have a 2wd lifted with 35s, why do you want to chirp the tires? Invested the money into that to abuse it?

 

still only a few hundred rpm's difference

 

Agreed, which is why I'll likely go with 4.88 gears even though I run 35s. I rarely see anything above 65-70 mph and I do a lot of driving at elevation and going uphill, so I figure the extra low gearing will help with that.

 

ya it is with my 33's with 3.55's turns a little over 2000 rpms at 80

 

go for 4.88s then and if you plan on upgrading to bigger tires then your good

 

I not apro here but here is my thinking from running my car down the track.
First of when you go to a larger tire your engine will be running at a lower rpm than the stock tire size. This is why you end up with the trans searching for its set points. (they were set at the factory for a certain RPM)
So if you go to larger tires to do the deal right you must change your gears to achieve return to the factory settings of engine trans RPM's at given speeds etc..
IF you tow (and I do) you will notice the difference from going from a tire size increase as small as 1". Any one who tells you otherwise is kidding themselves.
As for fuel economy the lower RPM's will help at highway speeds but hurt at around town driving so it depends on where you drive the majority of the time.
Like I said I am not a pro but the gearing issue is directly connected to the power the car makes. Larger tires changes your gearing, do the math.

 

I'm with mhockey. I had 35's with 3.73s, ran with them for about a year. Sure I thought they were fine but I didn't know what I was missing. I went with Yukon 4.88s and realized it's an upgrade I should have done sooner. I have 37s now and the truck moves better with the gears compared to when I had 35s. Yes, they are pricey but going big is not a cheap hobby. If you wanted to go with even bigger tires in the future, the 4.88s are a good choice.

 

Agreed as well. HUGE difference in power. When i hit the gas she moves very quickly. I always have chevys or dodges pull up next to me and just blow past them unless its a diesel haha. Always funny when their girlfriend in the passenger seat looks at my truck and smiles too when i hit the gas .... ill have to get some videos up of it

 

any suggestions where to get them? maybe a link for the 4.88's

 

I've been looking at Rons Machining service on ebay $775 for 4:56 or 4:88 that includes front and rears and install kits for each differential.