anyone running 4.56 gears?????
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anyone running 4.56 gears?????
hey is anyone running 4.56 gears and does anyone think that it would be a bad idea to go to these. anyone have any idea what shift points and other related parts would be affected or need to be adjusted.
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Originally Posted by ohohsilverado
hey is anyone running 4.56 gears and does anyone think that it would be a bad idea to go to these. anyone have any idea what shift points and other related parts would be affected or need to be adjusted.
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It all depends on what size tire you're running, and whether or not you do a lot of highway driving. Also what kind of gears you are currently running.
I have a tire that's over 31" and I do VERY little highway driving, so 4.56's were good for me, but maybe not for others. Ideally I wanted a 4.30, but nobody makes them for our trucks. As for shift points....YES they will need to be adjusted. Plus your ABS light will go off, and your speedo/odometer will be wrong. If you don't have a tune or means of tuning then you need to find someone or something that does. I didn't notice a drop in gas mileage at, and my rpm's on the freeway at 75 are about 2700. I recommend them for anyone with the good fortune of having an ECSB 4.8 with 20's or bigger.
edt: My gears don't make any noise at all....highway or street! But that's probably because they're set-up properly.
I have a tire that's over 31" and I do VERY little highway driving, so 4.56's were good for me, but maybe not for others. Ideally I wanted a 4.30, but nobody makes them for our trucks. As for shift points....YES they will need to be adjusted. Plus your ABS light will go off, and your speedo/odometer will be wrong. If you don't have a tune or means of tuning then you need to find someone or something that does. I didn't notice a drop in gas mileage at, and my rpm's on the freeway at 75 are about 2700. I recommend them for anyone with the good fortune of having an ECSB 4.8 with 20's or bigger.
edt: My gears don't make any noise at all....highway or street! But that's probably because they're set-up properly.
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Originally Posted by Soquel
I've heard that high of a gear ratio will weaken our rear ends. somtheing to do with the size of the gears.
What do you mean size? The 4.56's are not any bigger than any other gearset that's used in a 8.6" rear-end. They physically will not fit. I know offroading types run 4.56's and bigger all the time, and with +35" tires. If anything its the bigger tires that put extra stress on the rear-end, not the "size" of the gears.
#7
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Actually the 4.56 gears are marginally weaker because the pinion gear is smaller and the contact surface between ring and pinion is smaller.I've smashed everything in my rearend ,but never managed to break a ring and pinion gear 4.56 or other.
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This is true, contact area is different. I went with 4.11's in my car vs. 4.10's for this reason. But usually its the ring gear's teeth that will let go first. I think our stock axles/c-clips will go before a properly set-up aftermarket set of gears.
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Eat your beans http://www.4wheeloffroad.com/techarticles/3194/
Weak Pinions
As the ratio becomes lower, the size of the pinion gear and the number of teeth on it decrease. This creates more load on a smaller area, often causing teeth to break under abusive conditions. For this reason, 4.56 gears are the lowest available for some of the smaller axles (Dana 35s, AMC 20s, and some Dana 30s). Dana 60s and Ford 9-inch axles are strong and popular, so lots of ratios are available, some as low as 7.17. However, a 7.17 gear set is not as strong as a 4.56 set, or any higher ratio for that matter. If high horsepower and high rpm are used in the kind of four-wheeling that you do (sand, mud, wet rocks) you may be better off not getting the lowest gears possible. For other types of ’wheeling and daily driving, lower gears are a good idea
As the ratio becomes lower, the size of the pinion gear and the number of teeth on it decrease. This creates more load on a smaller area, often causing teeth to break under abusive conditions. For this reason, 4.56 gears are the lowest available for some of the smaller axles (Dana 35s, AMC 20s, and some Dana 30s). Dana 60s and Ford 9-inch axles are strong and popular, so lots of ratios are available, some as low as 7.17. However, a 7.17 gear set is not as strong as a 4.56 set, or any higher ratio for that matter. If high horsepower and high rpm are used in the kind of four-wheeling that you do (sand, mud, wet rocks) you may be better off not getting the lowest gears possible. For other types of ’wheeling and daily driving, lower gears are a good idea
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here is another vote for the 410's your highway gas mileage with be affected depending upon the speed you usually travel but it is a fact of life that at 80 currently with the 346 i run like 2200 rpm and like they say at like 75 they run 2700 rpm i am still gonna get some i just want to warn you about the mileage and hope you enjoy whichever ones you get i know i am gonna
oh and BTW
oh and BTW
Did you hear this from the same guy that sold Jack his beanstalk beans?