Highway speed/RPM question

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Fastbee

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Looking to purchase a 2007 Power Wagon with the G56 manual transmission. IIRC, the G56 doesn't have much of an "overdrive" for 6th gear. How would this truck behave on the interstate with the 4.56 gears? Not so much concerned with fuel mileage as much as being able to keep up with traffic or passing occasionally. I don't do much interstate driving in my trucks but would hate to get this one and find out I couldn't even keep up.
 

2003F350

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I think the G56's overdrive was something like .86? I can't recall. Either way, with 4.56 gears I wouldn't want to run over 70 for very long - just because it's going to suck down fuel like nobody's business. As for keeping up with traffic - you won't have any problems. That motor will be screaming but you'll be able to keep up.
 

akguy09

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Thats the best Combination of PW, if you can buy it, I would. It will keep up with traffic just fine

My First PW was a 2007 PW Reg Cab Long Bed
 

62Blazer

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Per Google the G56 had either a 0.74 or 0.79 OD gear. Combined with stock size PW tires and 4.56 gears you are around 2,600 RPM at 70 mph. I think you may not be putting in perspective the difference between 4.10 and 4.56 gears. 4.56 is not really that low and not much different than 4.10. You could cruise all day long at 70 mph and 2,600 RPM with no issues and I'm sure it could hit the speed limiter at 100+ MPH. My previous truck would run 2,300 RPM at 70 mph and it would spend hours on end on the freeway doing that.
 
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Fastbee

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Per Google the G56 had either a 0.74 or 0.79 OD gear. Combined with stock size PW tires and 4.56 gears you are around 2,600 RPM at 70 mph. I think you may not be putting in perspective the difference between 4.10 and 4.56 gears. 4.56 is not really that low and not much different than 4.10. You could cruise all day long at 70 mph and 2,600 RPM with no issues and I'm sure it could hit the speed limiter at 100+ MPH. My previous truck would run 2,300 RPM at 70 mph and it would spend hours on end on the freeway doing that.
Thanks for the reply, I had a diesel with 4.10 gears and a G56 that redlined at around 3k and 70ish mph. The tires were smaller and the diesel had a lower redline that the Hemi, I just wanted to confirm the 4.56 wouldn't give a similar result.
 
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Fastbee

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I think the G56's overdrive was something like .86? I can't recall. Either way, with 4.56 gears I wouldn't want to run over 70 for very long - just because it's going to suck down fuel like nobody's business. As for keeping up with traffic - you won't have any problems. That motor will be screaming but you'll be able to keep up.
If I don't buy this truck I'll most likely get a 100 series Land Cruiser...fuel economy stinks for both!
 

Lsujker

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This brings back a memory . Sorry, short story. In college my buddy had a 1995 Chevy single cab with 4.3l v6 and the manual. We drove it from south Louisiana to Tallahassee with cruise set at 99. The motor was screaming the entire way. If I remember, running around 3,600 rpm. No problems to or back. To be fair, probably the best motor GM ever made.
 
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ramffml

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This brings back a memento. Sorry, short story. In college my buddy had a 1995 Chevy single cab with 4.3l v6 and the manual. We drove it from south Louisiana to Tallahassee with cruise set at 99. The motor was screaming the entire way. If I remember, running around 3,600 rpm. No problems to or back. To be fair, probably the best motor GM ever made.

The 3800 would like a word with you...
 

Sherman Bird

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The 3800 would like a word with you...
Why? Both engines had turbo help in certain chassis. The Typhoon/ Cyclone trucks were stupid fast! I worked on one for Bo Orlando... Strong Safety for the Houston Oilers. That one had customized sound system AND was VERY fast!
 

ramffml

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Why? Both engines had turbo help in certain chassis. The Typhoon/ Cyclone trucks were stupid fast! I worked on one for Bo Orlando... Strong Safety for the Houston Oilers. That one had customized sound system AND was VERY fast!

Because it is built strong and will run forever. Obviously a bigger engine goes faster (with or without turbos), that's not the point.
 

StNick

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Your combination seems like it will certainly keep up with some traffic unless you are in California where most people drive closer to 80. If it ends up a problem then you could go to bigger tires or maybe even an auxilliary overdrive.
 

Bandit1859

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Looking to purchase a 2007 Power Wagon with the G56 manual transmission. IIRC, the G56 doesn't have much of an "overdrive" for 6th gear. How would this truck behave on the interstate with the 4.56 gears? Not so much concerned with fuel mileage as much as being able to keep up with traffic or passing occasionally. I don't do much interstate driving in my trucks but would hate to get this one and find out I couldn't even keep up.
Not well 456 gears we had a race car with those gears. Go to the high 300s gives you pulling power and better at 70mph
 

62Blazer

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Not well 456 gears we had a race car with those gears. Go to the high 300s gives you pulling power and better at 70mph
Out of curiosity, did this race car have an overdrive trans and how tall were the tires?
 

Daw14

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I’ve been running 4.56 gears with 33 “ tires and the six speed ,it’s about 2600 rpm at 80 Mph , 2750 at 86 mph . I’ve driven for two to three hours around those speeds and rpm in south Florida with no issues whatsoever. Overdrive sure is nice compared to the old days.
 

2003F350

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I’ve been running 4.56 gears with 33 “ tires and the six speed ,it’s about 2600 rpm at 80 Mph , 2750 at 86 mph . I’ve driven for two to three hours around those speeds and rpm in south Florida with no issues whatsoever. Overdrive sure is nice compared to the old days.
Aside from crappy mileage...LOL.
 
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