4.10 or 4.56?

[the_goat]

I want to go with deeper gears in my blazer now that I have a 700r4 instead of a th350. I'm going to stay with 33's and I have 3.73's now. What do you guys think? It's my daily driver. I know 4.56's sound really low but looking at the gear calculator it doesn't look to bad. Ideally, what should I be cruising at as far as rpm's?
Thanks

[Burt4x4]

Do you wheel any trails that requires you to crawl? Nice and slow and then goose it over stuff/obsticals? If yes get 456 if no get 410

[the_goat]

No, not at all. I was just looking at the rpms at different speeds with the different gears.
3.73's and the th350- 2600 at 65, the reason I swapped transmissions.
3.73's and the 700r4 -1750 at 65
4.10's and 700r4- 1900 at 65
4.56 and 700r4- 2100 at 65
I average around 50 mph to and from work.

[LONGHAIR]

My first thought is that you are doing this based on a "calculator". Probably using 33" tires as one of the variables? Are they? Just because that is the "size"....don't belive that it is accurate. You would be surprized at how far off inch sized tire measurements can be. Most 33" tires really measure around 31".
If the 1750RPM @ 65 is measured and accurate, you are defiantely too low in the RPM range, especially if you don't run that fast most of the time.
If you really don't drive many hiway miles, the lower 4.56 might be better. It will definately improve your in-town driving and mid-speed cruizing.

[sandking]

Where do I find this "calculator"?

[LONGHAIR]

Google something like "tire size gear ratio calculator" you will get tons of hits.

[the_goat]

I know it's just guessing with the calculator. I'll measure my tires tomorrow and take that into consideration.
Thanks for the replies.

[vtblazer]

On Randy's Ring & Pinion site, they give a range of 1800rpm to 3000rpm for cruising @ 65mph.

You'll like the combo, the 700r gives a nice 1st gear with a 30% over drive.

Given the option, I'd go with the 4:56's personally.