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No power driving up hill

Wes Harden said:
3.73 or 4.10 on 35s would be tough on some of those grades.
Those gears on 31s is a different story. Not to mention the weight savings going to a smaller tire
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All relative. It would be a speed racer vs 2.73 or 3.08 lol

I had 4.10’s and 42’s with a 700r4 and while it wasnt gettong up to speed fast, i never thought would this is a complete turd (expectations were low). I would think with 35’s and 4.10’s if everything was working properly it would kick down a gear and keep things moving
 
muddybuddy said:
All relative. It would be a speed racer vs 2.73 or 3.08 lol

I had 4.10’s and 42’s with a 700r4 and while it wasnt gettong up to speed fast, i never thought would this is a complete turd (expectations were low). I would think with 35’s and 4.10’s if everything was working properly it would kick down a gear and keep things moving
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A good buddy of mine back in the early 90’s bought a 1981 K-10 that came with a 305, TH350/208 and 2.56’s in the axles!
It was a PIG with 31” tall tires to say the least!
Within a few months we installed 4.10’s ( and a rear L/S ) with a 4” lift and 35” tall tires - it felt much better power wise but not great.

A year later he sold those axles and installed a set of CUCV 1-Tons ( 4.56’s ) an 8” lift and 39.5” tires.
It’s hard to compare just how pathetic the power would’ve felt compared with the 305 because we put a 454 in at the same time - technically it was still under geared but all that low end torque helped out quite a bit.

The moral of this story is that a less powerful engine will benefit from more gear to compensate for lack of grunt - something to consider when making a call on your gear selection.
If it’s intended to be an around town cruiser and hunting rig with minimal time at highway speeds don’t be afraid of a little extra gear.
 
Ok so I just rotated the tire and I put blue masking tape on tire and drive shaft and I rotated the tire and I got 1.5 turns on axle with 1 complete tire turn. Can someone tell me what gears I have please? Thanks
 
4.10

Just food for thought:
I’ve been running 4.10s and 37s for awhile, with a much warmer than stock small block
The low gear in the sm465 and the extra grunt are all that made that ok
 
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Im running 5.38 gears and with OD and my old 37s It was perfect on the freeway on the stock 350.... with no OD aka th350, I'd go 4.56 gears...
 
yes 4.10 ant 33-35s will work best with th350 trans and stockish 350. 35 and 4.10 will put you right at 2500 rpm at 65 beginning of good power in mild 350.
 
I didn't like 33's and 4.10. 55mph is like 1500 rpm in 4th and it just wouldn't pull out and pass until it downshifted, by that time I would have lost my opening or had someone rear end me, in so cal traffic. 4.1 in overdrive is the equivalent of 2.87 ring and pinion, worse than the 3.08 currently in the diffs. Hell 4.88 in 4th is 3.42's and 5.38 in 4th is 3.76
 
Just my $.02 worth - since you are working with ( and assuming you plan to stick with ) a very stock/mild smog era SBC with a non-O/D TH350 trans and desire decent get up-n-go for the hills, good power while hunting off road, and not a true highway cruiser your final tire size should determine the gear choice.

If a 33” tall tire is what you will end up with for the long run then a 4.10 is a nice compromise but if a 35” tall tire is chosen then a 4.56 is a fine choice.
Both of these scenarios will put you close to 2500 RPM’s at highway speeds and that’s where those motors start to feel confident and can handle some grades w/o the need for more pedal or gear changes instead of being at the very beginning of the power curve and needing to gear down for the hills - if the RPM’s are already in the power range the motor has a little in reserve to deal with some strain instead of lugging just shy of where it needs to be.

Make the gear change worth it instead of being on the verge of where you want to be.
 
Wes Harden said:
I didn't like 33's and 4.10. 55mph is like 1500 rpm in 4th and it just wouldn't pull out and pass until it downshifted, by that time I would have lost my opening or had someone rear end me, in so cal traffic. 4.1 in overdrive is the equivalent of 2.87 ring and pinion, worse than the 3.08 currently in the diffs. Hell 4.88 in 4th is 3.42's and 5.38 in 4th is 3.76
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I don't know how your experience was that way.
I had a k5, a suburban and a crew cab with that combo and the only time I didn't like the way it was pulling up the hills was the crew cab pulling the k5 on a trailer to Hollister.
The k5 had the th350 and it was running high rpm on the highway, I usually go 70-75, so I ended up putting a 700r4.
My suburban was a TBI 350, the other 2 were carbed
 
tarussell said:
Just my $.02 worth - since you are working with ( and assuming you plan to stick with ) a very stock/mild smog era SBC with a non-O/D TH350 trans and desire decent get up-n-go for the hills, good power while hunting off road, and not a true highway cruiser your final tire size should determine the gear choice.

If a 33” tall tire is what you will end up with for the long run then a 4.10 is a nice compromise but if a 35” tall tire is chosen then a 4.56 is a fine choice.
Both of these scenarios will put you close to 2500 RPM’s at highway speeds and that’s where those motors start to feel confident and can handle some grades w/o the need for more pedal or gear changes instead of being at the very beginning of the power curve and needing to gear down for the hills - if the RPM’s are already in the power range the motor has a little in reserve to deal with some strain instead of lugging just shy of where it needs to be.

Make the gear change worth it instead of being on the verge of where you want to be.
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I think I will end up with 33” tires once the 31” tires need replacing. I will most likely keep the th350 since the truck runs really good. Truck will be used for getting around town when I need to and camping/hunting so I think I’ll go for the 4.10 gear ratio. Thank you all very much for all your help I really appreciate you all
 
If sticking with 31’s for now, consider finding a set of stock axles with 3.73’s in them. You can likely find for $200-400 for the pair. Then later if you decide to step up in tire size, you can regear. I have 3.73’s with my 31’s and its a nice balance. That will be cheapest route vs having shop regear, and you dont need 4.10’s with 31’s that you plan to use currently.
 
This probably a dumb question but do I keep truck in 2H when driving on the 4x4 shifter or in neutral?
 
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