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Discussion Starter #1
would my truck be a lagging POS???

right now i have 7" kit with 35's and summer time im going to put 3"BL with 37s on it.. but then i got to thinking. SHIT will my truck be really laggy with the 37s on it or should the 4.56 gears be enough to suffice for that??

also i have this theory.. it seems like my 4.56's are overgeared for my 35s.. causing me to be over revs some times.. if i were to put the 37s on it.. could it actually cause my gas mileage to get a bit BETTER? or STAY about the same??? since it will be geared better..

:crazy: im trying to figure out whats best to do right now!
thanks guys
Kevin
 

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ive driven my friends truck with 37 iroks and 4.56 and it isnt as bad as i thought. He can still spin them easily.
I could live with 37s n 4.56...the 37's will only meausre about 36" too
 

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I've got 4.10s in my Blazer, with 36"tsls, and can still spin them around a corner from a stop. It is undergeared for sure, but I keep it out of overdrive 90% of the time and honestly it's not that bad. I would love to have some 4.88s or even 5.13s, but you will only be slightly undergeared with 37s and 4.56s, it will be fine :imo
 

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would my truck be a lagging POS???

right now i have 7" kit with 35's and summer time im going to put 3"BL with 37s on it.. but then i got to thinking. SHIT will my truck be really laggy with the 37s on it or should the 4.56 gears be enough to suffice for that??

also i have this theory.. it seems like my 4.56's are overgeared for my 35s.. causing me to be over revs some times.. if i were to put the 37s on it.. could it actually cause my gas mileage to get a bit BETTER? or STAY about the same??? since it will be geared better..

:crazy: im trying to figure out whats best to do right now!
thanks guys
Kevin
Hawk, Im in the exact same position as you right now. The only difference is engine (im tbi 350) I get that over rev alot, especially on the highway...So I'm also very interested to know and especially how it will effect gas mileage. It seems like the 37's wont run the rpms as high as 35's, thus resulting in better gas mileage!? right?:think:
 

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Ballin' on a Budget
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37's and 4.56's wouldnt be undergeared very far. my 35's and 4.56's seem pretty deep to me.
 

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GMFS slowest truck :read:
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what do yall consider over revving? seriously...the motors are spinning at 4000 rpms. YOU AREN'T OVERREVVING. 2500 rpms is fine on any motor. 4.56s and 35s is close to perfect...4.88s are nice for 36s and small 37s, then regular 37s or bigger, 5.13s...5.13s and 40s was undergeared a tad. Now im on 36s and it is a TAD overgeared, but doesn't overspin the motor by any means.

4.56s and 37s is just a little under ideal. not worth spending the money to get it redone tho, unless you can do it yourself.
 

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NCOR
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Im pretty content with 4.88's and 38's and my lower output motor. 4.56's and 37's sounds good to me.

Nick you may not be reving to high for the motor to cope but your producing more power than you need which is just wasteful, a 5.7L TBI on its way out vs. a 5.3L is quite a difference as Im sure you'll soon see.
 

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FWIW, I'm setting up for 4.56s and 37s as my DD setup.
 

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GMFS slowest truck :read:
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Im pretty content with 4.88's and 38's and my lower output motor. 4.56's and 37's sounds good to me.

Nick you may not be reving to high for the motor to cope but your producing more power than you need which is just wasteful, a 5.7L TBI on its way out vs. a 5.3L is quite a difference as Im sure you'll soon see.
lol im looking forward to extra power on tap. 36s are temporary too. They were there and were cheap...im not complaining. plus, they came right after the time i fugged my motor up bad, so yeah, 5.13s and 36s is great for now. I have a feeling ill still stand by what ive been saying tho. I drive a lifted solid axle truck...it isn't meant to drive over 70 really. itll actually have power at highway speed, not supersonic speed.

4.11s jsut aren't ideal for 35s. 4.56s is damn near perfect for them tho IMO. There has to be factors taken into all this consideration, but the Gen III motors are based off the ls1 5.7s...they are much more race inspired than previous gens. I agree that 4.88s with a VORTEC 5.7 and 38s would be a good combo. a lot of that has to do with it being an older motor that doesn't like to spin AS much and produces power a little earlier.
 

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i had 488s and trxus 36s that measured out to a little over 34s...loved it.
 

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Discussion Starter #11
Hawk, Im in the exact same position as you right now. The only difference is engine (im tbi 350) I get that over rev alot, especially on the highway...So I'm also very interested to know and especially how it will effect gas mileage. It seems like the 37's wont run the rpms as high as 35's, thus resulting in better gas mileage!? right?:think:

seriously, thats what i think...... but then again on street stop lights i think it may kill gas more..... LOL IDFK!!!! hahahah its confusing the hell out of me


what do yall consider over revving? seriously...the motors are spinning at 4000 rpms. YOU AREN'T OVERREVVING. 2500 rpms is fine on any motor. 4.56s and 35s is close to perfect...4.88s are nice for 36s and small 37s, then regular 37s or bigger, 5.13s...5.13s and 40s was undergeared a tad. Now im on 36s and it is a TAD overgeared, but doesn't overspin the motor by any means.

4.56s and 37s is just a little under ideal. not worth spending the money to get it redone tho, unless you can do it yourself.

I consider overreving when im on the freeway cruising at 2500 rpms or so, ill down shift to get around someone and it jumps to like 4600 or so and feels like it revs out real quick... then shift back to D and it feels low again... maybe im using the term incorrectly... but then again driving on the street D is sometimes too low so i down shift and it feels too high....:think: idk.. lol


To everyone else, thanks for your help.... this summer you will for sure see my truck on 37s now... wooooo
 

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Bayou Surface Drive, LLC
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I run it I like it. I will be pulling a trailer with 3 4 wheelers and ill let you know how it works.
 

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4.56s and small 37"s and love it.
 

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Bayou Surface Drive, LLC
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My 37's measure 35.5 on the weight of the truck and calculating in tire wear. they are close to 37 w/o weight. I like the combo. at 55 in od i spin 1663. 3rd gear at 55 is 2375. 60 in od is 1814 3rd gear is 2591, 70 in od is 2116 and 3rd gear is 3023. Its works well for me as im on the highway alot. Way better than my 3.42's i used to have
 

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I dont know if it helps but i got 37"s and 4.56s on my Ford. I am happy with it
 

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I think it would be ok. but that is comming from a guy that ran 4.10's on 38.5 It was a little slow on the takeoff but great over 70 lol.
 

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i have 37s and 4.56s and its not bad at all, however i still wish i had at least 4.88s but not near worth the hasstle of swapping gears again. but since you dont like the way your truck is with 4.56s and 35s, you will probably like it better with 37s and 4.56s imo. def no need to regear, just get the tires on there
 

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Discussion Starter #18
i think i will be doing this then.... only thing is what to do with the 35s..

anyone ever looking for some 35 all terrains that have like 7k miles on them...


i may have to wait and let the tread die out on these or somethin.. :/
 

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put em up for sale in the for sale section, maybe someone in your area needs em and they are members here
 
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