CK5
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38s and gears
- Thread starter ScottMH
- Start date
bigbadchev84
1/2 ton status
Depends on what your doing with it? I have 4.56s with my 38s and am really happy with them, I daily drive moderate trails and mud. I am pulling 14-15mpg Highway from them with my setup and keeping my foot out of it
Stomis
Professional Amateur
5.13s is way over kill for a stick truck on 38s. My truck has 36s and 3.73s and it feels perfect to me.
I would go 4.56s since your going to tow.
I would go 4.56s since your going to tow.
Depends on what trans you have in your rig, I have 38's and 4.10's with a wore out 305/400t and it does descent around town but on the highway it does pretty good. It ain't no hotrod but it will keep up with traffic pretty good, its a trail rig so I don't keep up with the fuel mileage with it.
Depends on the motor too.....
If you are way outside of the torque peak of the engine at highway speed, you'll get lousy mileage and it will feel sluggish.
A torquey motor will hide a lot of sins with bad gearing, but you'll still have a lot of residual transmission heat to deal with if you mismatch them too badly.
If you are way outside of the torque peak of the engine at highway speed, you'll get lousy mileage and it will feel sluggish.
A torquey motor will hide a lot of sins with bad gearing, but you'll still have a lot of residual transmission heat to deal with if you mismatch them too badly.
2BLAZERS
1/2 ton status
I have 38'' and 4.88 gears. I feel its almost too low for my worthless 350/350 combo at speeds above 45mph. It just runs out of rpm trying to keep up with traffic. In an ideal world I would have a bigblock with and overdrive tranny and 38'' and 4.88 would be awesome.
i currently have a 454 and a th400. i didnt build the motor so i dont know what its making, i do plan on building it in the future, going to shot for ~450hp/500tq, im thinking of putting a beefed up 700r4 or a overdrive on the th400, it cost almost the same haha
I had 4.10s with 38s and a small block turbo 350 203 other than the lack of gearing in the t-case for rocks this was my favorite gear setup ever.
Right now I have 4.56s w/42s and a doubler. Love this setup too. Sure isn't a hot rod around town but it will go 75 mph without a problem
Right now I have 4.56s w/42s and a doubler. Love this setup too. Sure isn't a hot rod around town but it will go 75 mph without a problem
Stomis
Professional Amateur
Id run 4.88s with an auto and a big block OD or not.
badmix
1/2 ton status
Im going to go with "depends on motor and tranny"
A 350 with a 700r, Id go into the 5:13s
A big motor with 700r, maybe high 4:88s
Anything with a T350 tranny, id go 4:88s or something in the 4:70 range.
But your intent determines alot as well. Highway running, trails, rocks, mud, desert, etc etc
I have 305cd, 700r and 33s with 4:10gears, IMO, this is a perfect DD combo.
A 350 with a 700r, Id go into the 5:13s
A big motor with 700r, maybe high 4:88s
Anything with a T350 tranny, id go 4:88s or something in the 4:70 range.
But your intent determines alot as well. Highway running, trails, rocks, mud, desert, etc etc
I have 305cd, 700r and 33s with 4:10gears, IMO, this is a perfect DD combo.
One thing that needs to be considered is what type of axle you are going to run this setup it.
If you are running a 1/2 ton or a 10 bolt, 4.10 is about as high as you can go with any tire over 35". After that you are looking at trouble.
Ideally you'd want the 14bff. I've ran 36" with 4.56s before in a 14bff, auto, and thought it was a great setup.
I'd say 4.56 or 4.88, anything higher would be overkill.
If you are running a 1/2 ton or a 10 bolt, 4.10 is about as high as you can go with any tire over 35". After that you are looking at trouble.
Ideally you'd want the 14bff. I've ran 36" with 4.56s before in a 14bff, auto, and thought it was a great setup.
I'd say 4.56 or 4.88, anything higher would be overkill.
BlackBourbon
1/2 ton status
Currently driving a Burb w/TBI350 700r4 and 4:56's on 39's and still can't use overdrive unless I am doing 90mph on flat ground haha.
Wish I was deeper
1BEATK5
1/2 ton status
if you are planning to add o/d, then just do 5.13s now and be done with it.
no o/d i think 4.88 would be better.
my previous combos
383/350/4.10, 38s. ok for freeway but made the 383 seem like a 350
350/350/203/205/4.88s 42s. 2600rpm at 60+, 260hp 350 spanked the 383
currently the 350 truck has 38s on it and does well. but could used o/d for a long trip.
i'm not sure this will actually help..... or make more
no o/d i think 4.88 would be better.
my previous combos
383/350/4.10, 38s. ok for freeway but made the 383 seem like a 350
350/350/203/205/4.88s 42s. 2600rpm at 60+, 260hp 350 spanked the 383
currently the 350 truck has 38s on it and does well. but could used o/d for a long trip.
i'm not sure this will actually help..... or make more
jtrapani
1/2 ton status
I've got a 383/350 trans and 203. Gonna switch to 4:10's and 35's I think. good combo? I'll eventually swap in a 700r
Stomis
Professional Amateur
4.10 and 35's is not terrible. It's a decent choice for no O/D. 4.56 is better, but that doesn't make 4.10 terrible.
jtrapani
1/2 ton status
well it'll be a while before I can get the new trans so Thats why I figured 4:10's. Its geared really tall now so it'll be an improvement.
jamcar
Registered Member
still pretty new here but for what its worth id go 4:10 woth 38's any higher and you might as well put in a 14 bolt ff
I have a 383/700r4/205 setup running 5.13 gears. Tires measure 37" to 38" tall on the rims I have. Turns 1800rpm to 2000rpm in overdrive at 70 mph.
