Rcv IWE eliminator kit

Downsides?

Slight hit in mpg.

It was talked about in these two threads.

http://www.fordraptorforum.com/f9/upgraded-iwe-20474/index23.html

http://www.fordraptorforum.com/f39/torsen-front-axle-problems-anyone-else-19867/index27.html#post798206

I ran my truck with no vacuum lines for 10k miles and only noticed about .2mpg loss

scarrjack said:

Downsides?

Click to expand...

MPG loss and drive train wear.

Keep this updated. Wanting to hear the results.

I personally would be more concerned about the additional transmission wear & tear. I guess we'll find out the real world lifespan/limits of those running it full time in the next 5 years.

From RCVs website:
Once installed, your hubs become fully locked to the axle shafts allowing you to use the transfer case to shift in and out of four wheel drive.

So can you switch back to 2wd or not? How? "Using the xfer case" is somewhat vague to me.

The way i understand it is when you switch to 2wd something within the xfer case disengages from the front wheels. But i am not sure

When in 2WD, the IWEs unlock to allow your front wheels to spin freely. If you unlocked the IWEs and pushed your truck down a hill, you could hold your half-shafts (front axle shafts) and prevent them from spinning while the wheels are still turning.

When in 4WD, the IWEs lock to allow your drivetrain to turn your front wheels. If you locked the IWEs and rolled your truck down a hill, the half-shafts would spin in your hand and you wouldn't be able keep them from spinning.

*Please dont try either of the situations listed above*

Using this same analogy, if you push your truck down a hill and your IWEs are locked, your front wheeks are turning and your half-shafts are turning so your torsen diff is also turning as well as your front driveshaft. Each of these components have either gears or bearings that generate heat when rotated due to friction. Heat is generated due to inefficiency (friction) which is why you loose MPG. The more heat, the more inefficiency, the more MPG loss. Each truck MPG loss will be different and depend on the toerances in your components.

Okay now the fun part. Axles have a ring an pinion gearset which connects the driveshaft to the half-shafts. Like all gearsets, one gear is designed to be the drive gear (pinion in this case) and one is designed to be the driven gear (ring gear in this case). If you are in 2WD with this IWE elimination kit installed, you actually reverse this relationship (the ring gear becomes the drive and the pinion becomes the driven). What does this mean? Well this changes the way the gears are loaded. So what? Right.

Well a few things can happen, the wear pattern can change on the gears (and bearings) leading to increased wear, decreased life and increased noise over the compoent's life. This can also cause increased service intervals for the front axle and reduce the life of the oil. The recommended oil weight and type is different for the front and rear axle (rear axle always turns when moving - front axle only spins when in 4WD) and might also be something you want to consider changing (changing the weight and going to synthetic) if adding this IWE elimination kit due to the increased duty cycle of the front axle (now always spins when moving vs. only spins in 4WD before).

---------- Post added at 12:33 PM ---------- Previous post was at 12:24 PM ----------

So purchase Joe's solution instead. Is that what that "like" means @HAYNES OFFROAD?


I havent tried either solution so please dis-credit everything I have said up to this point. Everything here on out will be the truth though.

Hahaha... Weeell.... I was just agreeing with your logic. But yea sure, buy my solution! Haha!

But yea seriously, the points @dkfc13 brought out are legit.

You assume some level of risk anytime you change the intended use of a component. Driving axles in reverse is not their intended operation even if you don't experience a failure. Make sure you evaluate the entire system before commiting to a change of this nature.


Okay enough of my drive-train non-sense.