4.10s or 4.56s ?

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shiftpro

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All depends what you're going to do with the truck too, if you're going to haul heavy loads you need a lower gear, no loads a higher gear.
Yes for sure but even a 0ne ton with big axles and lifted, big tires (wind resistance) and add some extras like winch and tools equipment whatever and there is a lot more weight to haul around. Again something like a hill at 60 mph and the overdrive may be thinking hmmm, 3rd..4th...3rd...4th. TC unlock...lock...unlock... frazzle!
 

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Yes for sure but even a 0ne ton with big axles and lifted, big tires (wind resistance) and add some extras like winch and tools equipment whatever and there is a lot more weight to haul around. Again something like a hill at 60 mph and the overdrive may be thinking hmmm, 3rd..4th...3rd...4th. TC unlock...lock...unlock... frazzle!

Exactly. You always want to keep it where it's happy, not where it's happy in some conditions.
 

74 Shortbed

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Yes for sure but even a 0ne ton with big axles and lifted, big tires (wind resistance) and add some extras like winch and tools equipment whatever and there is a lot more weight to haul around. Again something like a hill at 60 mph and the overdrive may be thinking hmmm, 3rd..4th...3rd...4th. TC unlock...lock...unlock... frazzle!
Well, lke I said you load it down definitely need a lower gear, and you won't be running in overdrive at 60mph only in 3rd and maybe lock the converter, maybe with a stout 540 or something but not with a stock 454, lol.. Myself if I had a one ton like that I'd put a TH400 and a GV in, had one in my dually and 6 speeds is badass..:D
 

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Because at 60 mph anything that looks like a hill or even a head wind and the 700r4 will be hunting back and forth between overdrive and third gear... and this creates nuclear meltdown in these transmissions.
Think about an overdrive transmission's final gear as 1 to 1. Set your final drive/tire height gear ratio in those terms.
And just because a BBC has the torque to lug a bit on the highway and get by with it... it can make matters worse as these overdrives (700 or 4l80)
don't like to be lugged.
Also the lock up converter if hunting back and forth makes big heat too.
At 60mph that would be 1800r's too low to even be in overdrive to begin with in a big truck, maybe on the flat with a tail wind or downgrade but that's it.
 

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Well thank you guys for the advice. I guess I will keep the 4.56 rear end and put it in maybe run it and see no it does. But don' want to burn up the trans that's forsure! I guess I'll wait to get the front regeared till I know forsure what I want In the rear. I could run smaller tires too which I guess is a simple solution i just want to fill the wheel well for the right look you know. Not to much space and not to little. If I' m towing and it's that big of a load I wouldn' probably be in overdrive anyways i would put it in 3rd or and not driving 70.
 

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Well, lke I said you load it down definitely need a lower gear, and you won't be running in overdrive at 60mph only in 3rd and maybe lock the converter, maybe with a stout 540 or something but not with a stock 454, lol.. Myself if I had a one ton like that I'd put a TH400 and a GV in, had one in my dually and 6 speeds is badass..:D
I thought a gv was 2 gears? It would be cool I agree but they are pretty expensive arn't they and don' you have to change the oil like every 1000miles someone told me that? I went the 4l80 route since I have it and the wiring for it plus I was hoping the overdrive would help with the mpgs I mean I know it won't be great big truck big block and big tires small price to pay for looking good right? Lol
 

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I thought a gv was 2 gears? It would be cool I agree but they are pretty expensive arn't they and don' you have to change the oil like every 1000miles someone told me that? I went the 4l80 route since I have it and the wiring for it plus I was hoping the overdrive would help with the mpgs I mean I know it won't be great big truck big block and big tires small price to pay for looking good right? Lol
Yes, but you can split each gear so you have 6 speeds, and the nice part is on the highway going up a grade instead of taking it out of overdrive and have rpm's to the moon, just drop it into second overdrive and keep your speed, yeah they are spendy but also pretty much indestructible, but if you can find an old wore out one you can trade it in for an upgrade, don't know what they give you now but when I got mine it came out just about half the regular price. They use gear oil and they're no different than a rear end with a posi, don't need to change it all the time..
 

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Isn't that the reason you can shift out of OD? If you a hauling a trailer, have a lot of weight and/or driving into a head wind, just take it out of OD and you will be fine.
 

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Yes, but you can split each gear so you have 6 speeds, and the nice part is on the highway going up a grade instead of taking it out of overdrive and have rpm's to the moon, just drop it into second overdrive and keep your speed, yeah they are spendy but also pretty much indestructible, but if you can find an old wore out one you can trade it in for an upgrade, don't know what they give you now but when I got mine it came out just about half the regular price. They use gear oil and they're no different than a rear end with a posi, don't need to change it all the time..

Duh haha I counted the 3 In the trans and 2 on the venders and got 5 not 6.
None of that sounds to bad at all. It might be something I will consider once it's done I mean should just have to bolt it on there and cut down the driveshaft not a huge deal
 

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Duh haha I counted the 3 In the trans and 2 on the venders and got 5 not 6.
None of that sounds to bad at all. It might be something I will consider once it's done I mean should just have to bolt it on there and cut down the driveshaft not a huge deal
Yep, it's a bolt on deal, the adapter takes the place of the tail housing and the mount is in the factory location, shorten the driveshaft done deal, and the electrics is plug and play super simple.
 

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A 6 speed TH400 would be cool! I bet that 2nd OD gear is nice. Crusty Biscuit's 3 speed manual with BW OD unit in 2nd OD is something like 1.17:1 ratio. Doesn't sound like much of a difference but it is noticeable and makes for a good downhill gear with the 4.57's.
 

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A 6 speed TH400 would be cool! I bet that 2nd OD gear is nice. Crusty Biscuit's 3 speed manual with BW OD unit in 2nd OD is something like 1.17:1 ratio. Doesn't sound like much of a difference but it is noticeable and makes for a good downhill gear with the 4.57's.
Yes it is very cool, I surprised quite a few people in my dually with a 11 1/2' camper on it towing the boat going up an on ramp, lol, that second overdrive sure was nice going up the grapevine too, lol..
 

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Yes it is very cool, I surprised quite a few people in my dually with a 11 1/2' camper on it towing the boat going up an on ramp, lol, that second overdrive sure was nice going up the grapevine too, lol..
But then again you weren’t towing a scooner either your kind of boat can’t weigh to terribly much lol
 

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