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Discussion Starter · #1 ·
Hey guys...

getting ready to do my 4.3 -> 6.0 swap, however going to do gears and an ezlocker first... I was planning on doing 4.10 gears as in my previous experience, the motto was dont fear the gear. This will be a DD, and i will be running a 4l80E with a 3200 stall... too much gear? Should i be looking into 3.73? Thanks.
 

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GMFS slowest truck :read:
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what size tire? the 4.10s will be much nicer with the 80es first gear...but the higher OD gear kind of hurts too, depending on tire size. How much highway, etc? Personally, i like deep gears for DD purposes, but mines mostly street driving.
 

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Discussion Starter · #3 ·
The tire will be a 255/45 on a 20" rim. It'll be 80% city streets, 20% highway... if we do highway driving already, wife drives her 350z.
 

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i ran 410s with my old setup and was crusing at 2200 rpms at 70mph with a 30" tire

if i was going to do ti again i would of went 430s to help with 1320 performance

you should be fine knowing the 80 robs so much and has horrible stock gearing for NA applications
 

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HOT AIR BALLOON OWNER
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You're going to be at 2400rpm @ 70mph with a 30" tire and a 4.10:1 with the 0.75:1 OD of the 80E. Bit high for my taste on cruise RPM.
 

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Discussion Starter · #8 ·
You're going to be at 2400rpm @ 70mph with a 30" tire and a 4.10:1 with the 0.75:1 OD of the 80E. Bit high for my taste on cruise RPM.
255 works out to be just about 29" tall, which will put me about 2250?

I wonder if they make somewhere in the middle of the road 3.90s for these trucks, like they do mustangs. search time.
 

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HOT AIR BALLOON OWNER
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255 works out to be just about 29" tall, which will put me about 2250?

I wonder if they make somewhere in the middle of the road 3.90s for these trucks, like they do mustangs. search time.


Uh no, smaller diameter tire (rotates faster) = higher RPM. 2494rpm @ 70mph.

Yes, a 3.90:1 gear set is made.
 

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just do 410s
 

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HOT AIR BALLOON OWNER
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I'd run less gear, go with a 3.55:1 or a 3.73:1, that's pretty stout cruise RPM. If you're that concerned about launch, spend a few extra bucks for the wide ratio gear kit for the 80E.
 

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could always just run a taller tire on the street for cruising. and personally i owuld rather be around 2-2200 rpms while crusing

less your gear ratio and the ride falls on its face in the 1/4
 

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Left Jizz
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2500 rpms isn't going to hurt anything cruising down the highway. He already stated that only 20% of his driving is on the highway. 4.10's should get better mileage in town due to less force needed to start things rolling. Alot of 6.0's came stock with 4.10's and the 80E from the factory so it can't be that bad of a combination. Plus the 4.10's will allow for the extra rotational mass of those 20's.
 

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HOT AIR BALLOON OWNER
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2500rpm on the freeway is going to hurt your economy and is unneeded wear. 2000-2200 is far better for the freeway, I think we all agree on that.

Also, too much gear can be bad for in town cruising. I prefer to keep the vehicle in whatever gear is direct (1:1) so it is not constantly shifting in and out of OD. I figure 50mph I can handle about 2000-2200rpm there, so around 40mph it's even less.

If you're overgeared, you'll have OD engaged and have you at the bottom of your powerband and without you'll rev too high. Just something to think about.
 

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Dont the 1500HD come stock with 6.0L 80E 4.10s and 245/75/16 tires? I dont think it would be too much gear.

Edit: ooops haha didnt realize this thread was old as fuck.
 
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