gearing questions

[quikdrummer]

Hi guys have another set of questions for you

My bro in law can get me a set of 5:43 gears for my rear end, free of charge. Im worried that might be too low for my current setup and would need to do a bunch of other upgrades to get them usable.

Heres my setup: mild 302, stock 3-spd, 9" rear end with stock gears, stock Dana 30 up front, stock Dana t-case, 265/75R16 tires which are right at 31 1/2" tall at 20 psi. I drive the truck around town and on the trails, never on any freeways, never get above 60 mph.

Does anyone have that gear ratio? If so what other drivetrain upgrades have you needed to put in? Also is that ratio easy to find for the front 30?

Any answers would be great!

 

[Doyle]

With that gear ratio and tire size you'll be near 3500 RPM at 60 MPH. You might want a taller tire.

 

[broncnaz]

I wouldnt go that low with those small tires. One day you'll want to go on the hiway. Those gears are better suited for about 40 in tires. but there are gears availible for the front D30 to match them. So you could go that route but more than likely you will need to change the front carrier unless you already have 4.11 gears in your axles. Theres also a good possiblity that with that gearing your break front axle shafts easily.

 

[quikdrummer]

thanks for the answers so far guys, im still debating.

i found a R&P set from complete offroad but its almost $300

add that to the cost of new tires and it may be a future project...

 

[Apogee]

Gears that low in a Dana 30 seems like a bad idea from a longevity stand point, but I can't say I've ever seen one set up so low though due to the tire size versus top speed concerns. Like 'naz mentioned, that gear ratio is more often associated with 39 inch or bigger tires and you'd have to be incredibly optimistic to think that a D30 will hold up to anything that size if it's actually driven in 4WD anywhere (mall crawling aside).

You can find used front and rear sets in good condition and more reasonable ratios through many of the off-road classifieds either here or on other forums, as well as Craigslist and such. You should be able to pick up used gears relatively cheap and then will just need the install kit.

 

[broncnaz]

Dont forget you'll need new bearings and a setup kit($100 or so) and the new carrier(open $60). New bigger tires might mean bigger lift also.
When it comes down to it you might be better off $$ wise with a transmission swap like a NP435 it will give you a good low first gear for offroading. And will be cheaper that swapping out gears.
Personnally if swapping out gears you may as well put in lockers at the same time. Then its usually a good idea to upgrade your axle shafts also. It pretty much snowballs if you want to do it right.

 

[needabronco]

I would look at a transmission swap before I went that low. NP435's seem pretty easy to come by around here. The yard in Chino is pretty good to deal with, and they generally have a good selection.

If you already had 35's and and OD trans, gears that low would be OK if you never drove on the highway, but then your limited to local trails or trailering. We wheel all over the place and like to drive their. Flagstaff isn't that far in the summer and Phoenix isn't either for winter runs. Just something to think about.

With your setup I'd look into a locker first.

 

[quikdrummer]

It pretty much snowballs if you want to do it right.

i hear you there

i already have a lock-rite in the rear end. and the stock gearing is relatively low already so its not a slug offroad. i just had the oppurtunity to get the gears for the rear free and so was wondering if it would be a good idea.

but along with these replies and some of the other research ive done i think it would end up being way more expensive to get the gears to be useful

thanks again for the response