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What's the difference? 2004 Honda CR-V cam-driven AWD and 2005 hydraulic pump AWD

What is the difference between the 2004 Honda CR-V cam-driven AWD and the 2005 hydraulic pump mechanism AWD?

Internet search doesn’t show anything. Only : “A new, smarter, cam-driven 4WD system replaces the outgoing hydraulic pump-type mechanism.”

Why is the cam-driven “smarter” and better? How does it differ from the hydraulic pump type?

Will one be more difficult to repair/maintain than the other?

My daughter had the older version. It seems that the drive shaft on the older version turns off the front differential constantly with a clutch that is activated in the rear diff by hydraulic pressure as needed from the front drive train. Know nothing about the “cam version” of 2004 (?)

The newer 2012 version is in all probability controlled by wire from a computer after input from sensors, more like “everyone” else. That should mean, like a RAV for example, it’s more seamless. Since the RAV, Subaru and others are virtually bullet proof, I doubt there will be a reliability difference.
Do you like wires and actuators or hydraulic lines and slave cylinders and potential leakage…your choice. I wouldn’t worry from a maintenance point from any system but expect performance in 2012 now on par with the better AWD units which was lacking in the past.

I’m considering the purchase of a used 2003-2006 CRV.

Just wondering if the change to cam-driven AWD in 2005 was significant enough to affect my choice of that model year over previous ones.

I’m also intrigued as to why I cannot find any literature outlining the difference between the cam-driven and hydraulic pump versions of the CRV AWD systems.

You may have gotten some bad info. There may have been a slight redesign of the AWD system, but as far as I know, it has always been, and still is, a hydraulic clutch system that senses a difference in wheel speeds between front and back. Here is a description of the system. Not clear what the date of this info is, but by the photo it appears to be a very recent model year.

PS…that article describes a ball cam mechanism that “augments” the hydraulic system. That seems to be what you read about. I believe the ball cam mechanism does not exist in earlier models (like my 1999 CRV), so the addition of the ball cam mechanism may have occurred in the 05/06 model years you’re looking at.

But basically, the mechanism is still mainly the old proven hydraulic system with some bits added. I’ve never heard of a problem with it.

All you need to do is make sure to change the differential pump fluid at recommended intervals with genuine Honda fluid and you’ll be fine, with or without the ball cam mechanism.

Thanks jesmed, Some great info.

The photo with the article you referred me to looks like a Fourth Generation CRV.

Your '99 is a First Gen. and I’m looking at the 2nd Gen models which ran from '02 to '06.

Midway through these 2nd Gen models some significant changes were introduced in the 2005 model year. A 5 speed auto replaced the previous 4 spd, (giving slightly improved mpg), traction control and Vehicle Stability Assist were also added along with the “smarter, cam-driven 4WD system” under discussion.

While the article you listed does seem to explain the cam-driven details of the AWD system and its control of the hydraulics involved, if it is, in fact, referring to the 4th Gen models, it still leaves some questions about the specifics of the '05 models.

Here’s what I found in Wiki’s vague explanation of the 4th Gen “all-new Real-Time all-wheel-drive (AWD) with intelligent control system”.

“The 2012 CR-V was launched at the 2011 Los Angeles Auto Show[19] and it is powered with a 2.4-liter i-VTEC inline-four engine that puts out 185 hp and 163 pound-feet (220Nm ) of torque at 4,400 rpm along with an all-new Real-Time all-wheel-drive (AWD) with intelligent control system.”

Sometimes the tech notes don’t explain nearly as much good ol’ real life experience.

Comments from owners like you offer an earthy quality of reassurance that is unmatched by engineering stats-

"But basically, the mechanism is still mainly the old proven hydraulic system with some bits added. I’ve never heard of a problem with it.

All you need to do is make sure to change the differential pump fluid at recommended intervals with genuine Honda fluid and you’ll be fine"

Ah, I’ll be fine. That’s what I wanted to hear. Now if I can just get a seller to commit that to writing. There I suspect the “Ah” will change to “Nah.” Yah?

Thanks again jesmed for your helpful advice and research.