66RFE performance builds

ksonnen1

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Has anyone built a 66RFE to withhold 600RWH or have any good suggestions on builders?
 

Burla

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Sharadon is a good name, although don just retired, look into them. Sun Coast does rfe's up to 950hp, but mainly the 68rfe or anything hanging off a cummins.
 

ksonnen1

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Sharadon is a good name, although don just retired, look into them. Sun Coast does rfe's up to 950hp, but mainly the 68rfe or anything hanging off a cummins.
thx.. I did call suncoast disel and they only sell the rebuild kits for 66RFE and not the actual builds. 68RFE they do builds
 
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Burla

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thx.. I did call suncoast disel and they only sell the rebuild kits and not the actual builds.
? That's crazy, here is their product line. Seams like the entire world took a dump and nobody feels like doing anything. If you can talk them into it - it would likely be 10 grand for the 66. I'd try begging :)
 

Wild one

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Has anyone built a 66RFE to withhold 600RWH or have any good suggestions on builders?
Nobody has a reliable RFE,no matter how much money they spend. Check out High Performance Rams and Tuned Rams on facebook and ask about building a reliable RFE on those pages. The higher power guys usually keep a stock of used ones on hand,or else swap to the 8 speed/Turbo 400 or 4L80 (GM trannies) and some guys are swapping in 727 or 518's (Chrysler trannies). The RFE was originally designed for the early low horsepower 4.7. Lay in a stock of used ones,get good at swapping them,and learn how to drive to keep the tranny alive,and they're usually good for a few months behind a semi high horsepower engine. Do not do wide open downshifts (like passing on a 2 lane highway),get in the habit of manually down shifting it prior to going wide open,and no high speed runs in high gear.The transmissions will last as long as you drive them to keep them alive.They're okay from a dig ,but not good from a roll
 
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2012RAM1500RT

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I don't have a race truck or high horse power engine but I have 2, 2012 Rams. One is a 1500 5.7 Hemi with the 65RFE with 137,000 miles and one is a 2500 5.7 Hemi with the 66RFE with 216,000 miles. Personally I prefer the 66RFE over the 65RFE because the difference between 2nd and 3rd gear on the 65RFE is a joke. I drive both of them just like anything I've ever owned, I push them to their limit a lot. "Knock on wood" I guess I'm one of the lucky ones but so far both of them has been flawless. Has so far given me no reason to feel like they won't go many more miles. They could go out tomorrow who knows. I've always preferred manual transmissions anyway cause I've always experienced the weakest link in a drivetrain "for me" is an automatic transmission.
 
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Bigskyroadglide

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I have adopted the practices that Wild One indicates. On my 2011, I manually downshift with the shifter lever before passing and on high speed runs, I know there's a possibility of damage so I try to stay under 120 mph.

My 11 has been serviced routinely ever 30k and at 150k. It's primarily a tow vehicle, for my 7x14 trailer.
 

jambbii

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Anyone that builds the 68 should be able to help you....There are a fair amount of diesel builders out there. The 66 shares a ton with the 68. I plan to build mine eventually when I start making some power. Might try reaching out to Sonnax and see if they have any builders they recommend in your area.
 

RLJ10X

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Its best to do as W1 advises and just not beat on the 5/6 speed.

Just my humble opinion, but these trucks come out geared too tall for that transmission. Tall gears are extra stress on an already marginal transmission. Guys like big tires; more stress. With the big tires, the truck gets sluggish, so then Headers, CAI, and tuner are added for more power. A bad situation just got worse. Throw on a little "spirited" driving, and you know the rest.

Give me 3 petals and a stick, please.
 

2012RAM1500RT

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Its best to do as W1 advises and just not beat on the 5/6 speed.

Just my humble opinion, but these trucks come out geared too tall for that transmission. Tall gears are extra stress on an already marginal transmission. Guys like big tires; more stress. With the big tires, the truck gets sluggish, so then Headers, CAI, and tuner are added for more power. A bad situation just got worse. Throw on a little "spirited" driving, and you know the rest.

Give me 3 petals and a stick, please.
I agree with the 3 pedals and a stick 100%. I personally would never pick "any" automatic over a manual if given a choice! JMO!
 
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