2003Silvyrado

If taller gears are so great then why do all the dragsters with $50-100k cars with their Ford 9" rears all use at least 4.11s or even deeper gears? They do this even with 3 speed automatics.

When I swapped I lost no mileage. I didn't really gain any either. With the 3.42s speed changes involved alot of downshifting, and more pedal, sucking gas. The only way I'd lose mileage is at constant speeds, like on the freeway, and I still get 20 mpg. Driving in stop and go I get between 18 and 19 mpg.

If I had 3.73s I would not swap to 4.10s but I had 3.42s and they sucked. Who cares if you can beat someone on the freeway. Freeway racing is dangerous anyway. Having said that I would've loved to have lowered my truck and wrapped some low profile tires on my 16s. That would've let me save a bunch of money on the gear swap and would've given me the same effective ratio as my 4.10s now.

Then again 16s with low profile tires would look funky. I'd still have done it though. Its easier for a vehicle to be twisting little wheels and tires with 3.42 gears than it is to be twisting bigger tires with 4.10s.

Tires between 24" and 25" with 3.42s would've done the same thing for me as my 4.10 gears with tires between 30 and 31 inches.

Wait now I remember why I swapped the 4.10s in. My 3.42s had no posi. The only difference in cost was the price of the gears. 3.42s with short tires would've been a bitch to hookup with only one wheel putting the power to the ground.

snoman

What logic are you using here I wonder. 25 years ago I had a old 72 GMC 3/4 ton 4x4 with a 350 4bbl and 4speed and it would top out at 115 to 120 with its slow 4.10 gears and could cruise as fast as you carried to drive it all day long without breaking a sweat. (and today you have OD to which would make a 4.56 feel a lot taller than my 4.10's did then) Somewhere in your mind you think that gassers make their best power and performance under 3000 RPM. Boy did you miss the boat, I think you need to go to a diesel forum wherer 3000 is the redline and gearing is this limited.

MacADaYear

You show me where I think the best performance and power come from under 3000 rpm? Are you fuckn stupid? I never once said that and plan on revving my 4.8 to 6500+. All your doing is pulling **** out of your *** and making yourself look more stupid. Give it up genious.

snoman

You say it by your insisting on taller ratios than is really needed for a big heavy 4x4 truck with big rubber. Your temper shows this too. Yuu want your engine near or at its torque peak at your best cruising speed with big rubber and not 1000 or more RPM under it and with a OD that is next to worthless too.

MacADaYear

You have no idea what you are talking about old timer

snoman

Young timer, you are to one that is REALLY clueless here.

TigerFan187

iTrader: (1)

OK for those who think that 3.42's are faster than 4.10's-I think I read in on of those post- its all blury now I went to the 1/4 strip for about 8 weekends in a row and raced everyone one(im sick) This is in the middle of the summer so temps where the same 90's before sundown and 88 after and wet humidity- My truck came stock with open diff & 3.42's(if I only knew what I do now) and with my current mods less the n20 I was running 16.2's(best) constantly for 5 Fridays in a row. I got my 4.10's(didnt do a posi) and went to the track that following Friday and ran 4-15.8's and 2-15.9's. I went back the next 2 Fridays and ran 3-15.8's and 1-15.9. No matter what you say on the 1/4 mile 4.10's are quicker/faster than 3.42 and I assume 3.73- If you need videos or time slips I have.

snoman

With better launch traction you should be able to take another 2 to 3 tenths of of it as you "dial" it in better.