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What's your opinion on the g56? Can it handle the same power as the 68rfe? Just planned to delete and 30-60hp tune. Everyone says throw a southbend in but I want to know what the tranny can safely hold.
how much power can g56 safely hold?
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From what I have read the manufacturer rates the g56 up to 600 ft lbs of torque which who knows if that's accurate or not. From personal experience though, mine is a 2015 and its fully deleted with anarchy tunes. On the 100hp tune in 5th and 6th gear if I hammer on it the clutch slips pretty good. Ever since I bought my 5er that weighs 11,500 unloaded and 16,400 loaded on a 90hp tune it slips pretty good in 4th and up. I just ordered a Valair Quiet organic dual disk Clutch that's rated to 550hp. I would say if you have the money I would throw a goos single in or dual in depending on future plans and never have to worry about it!
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It’s not the transmission that’s the problem. It’s that the clutch will start to slip. This is why they are tuned for 660ft/lbs from the factory.
It’s a crap shoot man. My first g56 truck delete didn’t make it a block before it slipped in anything above 3rd. 75hp tune.
This truck I drove for a few weeks before swapping the clutch. Even towed a little. However, I left it on the stock 0hp tune. Even with that if I got more than about 3/4 throttle in 5th towing it would slip a little even with an empty trailer.
Just do yourself a favor and plan on adding a decent solid flywheel style clutch when you delete if you want to get full use out of the truck. Some guys, one in particular, are able to get by. However I guarantee they can slip their clutch if they tried. They just drive around it and use light throttle.
It’s a crap shoot man. My first g56 truck delete didn’t make it a block before it slipped in anything above 3rd. 75hp tune.
This truck I drove for a few weeks before swapping the clutch. Even towed a little. However, I left it on the stock 0hp tune. Even with that if I got more than about 3/4 throttle in 5th towing it would slip a little even with an empty trailer.
Just do yourself a favor and plan on adding a decent solid flywheel style clutch when you delete if you want to get full use out of the truck. Some guys, one in particular, are able to get by. However I guarantee they can slip their clutch if they tried. They just drive around it and use light throttle.
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you're off your rocker saying 750whp it would sound like a garbage disposal filled with pennies.
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So... you have no idea how much the G56 can handle with a stock clutch. Come on here asking for advice. Get a fairly valid post from someone, and then proceed to criticize it?
These things with just a tune are in the 500whp/1000 ft/lbs ballpark. The numbers he posted aren’t that astronomical.
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The g56 itself can handle a lot more than the small tune youre looking to apply to it. The stock clutch in front of the g56 cannot. Plan to add a clutch to the tune bill. But to answer your actual question, the g56 itself can handle lots and lots and lots more power than a little tune will make.
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I by no means am saying that I know anything about the g56. 750 wheel seems like a stretch though. Does anyone have any experience with southebend or some of the other aftermarket options?
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Wow..... my bet is the stock clutch can hold up the 60hp tune. And do a good job. Depending on tire set up and the nut behind the wheel.
The G56 can handle what you plan.
I have a valair dual disk org and run a 100hp tune and drop to the 60 while towing. Does just fine. Nice thing is I can actually shift tunes at will and dont have to worry about the trans relearning anything.
Can you blow up the G56, heck yeah, will ya do it with a 60hp tune, probably not unless the person controlling the inputs does some messed up stuff.
Do some searching around on the forums. Many have put a ton of miles on these trans with all kinds of power levels. A couple have got junked (the couple I read about were doing boosted launches with high power). There have been a few issues just like with anything thats man made.
Grab a good clutch, some good fluid, a tune, and worry about some of the other stuff that can go wrong. (IMHO).
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if you look up the G56 transmission i believe it's rated for 700lbs
either way, i run a tow tune on mine and a DD organic clutch and it's been fine, i guess? i dont race just the occasional towing. im confident that the g56 will hold a tow tune with zero issues and wont shorten it's life span.
BUT..if you do get a tow tune and run a single mass flywheel, that chatter you hear in the low rpm range WILL slowly kill your transmission. thats basically the sound of your gears smashing into each other. i've seen guys who lugged their G56 its whole life with a single mass flywheel and the gears were missing their teeth due to 200,000 miles of smashing into each other.
either way, i run a tow tune on mine and a DD organic clutch and it's been fine, i guess? i dont race just the occasional towing. im confident that the g56 will hold a tow tune with zero issues and wont shorten it's life span.
BUT..if you do get a tow tune and run a single mass flywheel, that chatter you hear in the low rpm range WILL slowly kill your transmission. thats basically the sound of your gears smashing into each other. i've seen guys who lugged their G56 its whole life with a single mass flywheel and the gears were missing their teeth due to 200,000 miles of smashing into each other.
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I thought the chatter was from the single mass flywheel not isolating the vibrations from the engine. The issue is always there, it’s just the design of the dual mass quiets it down. Dual disk exaggerates it because of the added parts to rattle. Your description makes it sound like there is a ton of slop in the gears and they don’t mesh right. Which means it would be a problem with dual mass, solid disk, or dual disk.
I could have misunderstood your explanation as well
I could have misunderstood your explanation as well
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dual mass flywheel keeps gears meshed together by continuing the momentum/energy of the engine between combustions. there isnt slop, but all gears have backlash otherwise there would be extreme heat and wear issues. if you ever set up a rear end and check the lash of your pinion to ring gear, just by moving it with your hand .005 of back lash can be heard VERY clearly. so that chatter is from the few thousandths of an inch of backlash.
hence, gear roll over is much louder at low RPM because of the timing between each combustion, at higher RPM the engine is able to smoothly transmit power to the transmission and through the gear train which results in less gear noise.
you can put a single mass flywheel with a single disk clutch and it will do the same thing, this applies for all transmissions because they all have backlash set into the gears. its more pronounced on a G56 due to the aluminum housing
https://en.wikipedia.org/wiki/Dual-mass_flywheel
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Ok yeah my bad. I wasn’t thinking backlash. My brain was thinking you were saying there was so much slop that the gear teeth were essentially smashing together each time they meshed.
You are the first person I’ve read though saying it can destroy the gears. Most things say it’s perfectly fine don’t worry about it. Good to know there are actual instances of it causing damage
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happy to hear everything's working out for you guys on the new clutch. Would it be reasonable to assume I can get away with the stock clutch on a 30 tune like previously mentioned? This will be a daily/work truck I'm looking for tractor like reliability.
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it was only one instance i saw on pirate4x4.com where a guy bought a used 6.7 that was used as a hotshot truck (had high miles) and it must've been lugged around a lot. i think the only way he found out the teeth were smashed that he opened up the tranny, i believe the truck still drove around fine.
im sure more exist out there but it's one of those things you'll never notice until you crack it open
found the thread.
my previous details i described earlier might be off as i read this over a year ago. sounds to me like he really didnt know how to drive the truck properly once i read he was complaining about gear rollover at 4th and 5th below 1400rpm.
https://www.pirate4x4.com/forum/tow-rigs-trailers/2340617-diving-into-400k-g56-trans.html
Meh, maybe for a while. That's the nice part. Drive it til it start's slipping then baby it until you drop in a new clutch.
I know one guy who got 100k out of his OE G56 clutch. Bone stock, commuter truck and he'e not a gearhead and drives like my gramma. He roasted the clutch immediatly upon putting a tow tune on it after the warranty was up.
You can daily drive/work the truck with a little tune for quite a while (idk if that's 10min or 10kmiles or 10 years) if you know what you're watching out for. No full throttle above like 4th gear (for a 30hp tune). Basically pretend it's stock.
I've only driven my 07 G56 long term, but the writing is on the wall. Plan for it. It's like needing new tires.
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i didnt even bother running a stock clutch. I installed a Valair DD a week before deletes because i really didnt want to deal with it. not saying it wouldnt have held it, i just didnt feel like chancing it
Yeah I could see that doing it. His trans must of been making one hell of a racket if he was giving it any amount of power or going up any incline at that rpm. Thats one reason I dont let anyone drive my truck now that I swapped out the clutch. Hope I never get a recall that requires me to take it to the dealer (bad enough that it actually needs to get done and I cant do it myself).
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