A/C sucking engine power

psdtime

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Joined
Feb 19, 2019
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Location
California
I flat towed with my motorhome my Jeep to my favorite camp spot last weekend, and since we got there way before the rest of our guest, we decided to take the LJ for a cruise to town for lunch and urban exploration. It was 102 degrees, and although I only had a bikini top on, I wanted to run the A/C for us and the kids. I know that using the A/C adds more load on the engine, but the power loss was pretty dramatic. I started to turn the A/C off anytime I saw a small grade or a highway onramp. Without turning it off, I might only be able to hit 35mph on the onramp, with it off, I could pretty easily hit 55mph. This was on the Central or Southern Coast of California, so I'm only looking at about 1000' of elevation max. Does this sound normal?
The Jeep is a 2005 Rubicon LJ with an Auto, 33' tires and 5.13 gears.
Thanks
 
At low RPMs, the A/C often takes up a sizeable amount of power relative to what the engine can put out at those speeds.
If you force the transmission to downshift (by turning off OD or putting it in 2nd even) and accelerate at 3000+ RPM, is it as noticeable?

With my six speed, it’s only noticeable below about 1700 RPM. I cruise at 2700 on the highway with my stock gear ratios and tires so it’s not noticeable then.

At very high RPMs, many A/C clutches disengage to prevent damage to the compressor. This also leaves more available power for acceleration that is not available at lower RPMs. (I don’t know if this is the case in the TJs.)
 
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I flat towed with my motorhome my Jeep to my favorite camp spot last weekend, and since we got there way before the rest of our guest, we decided to take the LJ for a cruise to town for lunch and urban exploration. It was 102 degrees, and although I only had a bikini top on, I wanted to run the A/C for us and the kids. I know that using the A/C adds more load on the engine, but the power loss was pretty dramatic. I started to turn the A/C off anytime I saw a small grade or a highway onramp. Without turning it off, I might only be able to hit 35mph on the onramp, with it off, I could pretty easily hit 55mph. This was on the Central or Southern Coast of California, so I'm only looking at about 1000' of elevation max. Does this sound normal?
The Jeep is a 2005 Rubicon LJ with an Auto, 33' tires and 5.13 gears.
Thanks
Did you find a solution?
My 1999 TJ has the same problem,