Need a quick tow package answer

[wchevron]

How does the larger alternator and fan help with the towing? Only ask because I just added a hitch to my Rubicon and will be towing about 4200lbs a couple of times next summer. Wonder if I need to upgrade the two?

Sponsored

 

[ecidiego]

How does the larger alternator and fan help with the towing? Only ask because I just added a hitch to my Rubicon and will be towing about 4200lbs a couple of times next summer. Wonder if I need to upgrade the two?

The fan is for increased cooling capacity. 850 versus 600 watts. The blades are much wider, I am sure the CFM change is large. It will pull a hell of a lot more air through the radiator fins. The alternator is needed since the fan greatly increases the amperage draw enough where Jeep doesn't feel the base alternator is good enough.

At 12vDC:

600w: 50 amps
850w: 70 amps

 

[JRobes]

The fan is for increased cooling capacity. 850 versus 600 watts. The alternator is needed since the fan greatly increases the amperage draw enough where Jeep doesn't feel the base alternator is good enough.

I'm not so sure the difference in amp draw between fans is all that different; I'm guessing the main reason for the larger alternator is to keep up with any potential electrical draw from your trailered vehicle (ShadowsPapa confirmed below this is up to 30 amps).

 

[ecidiego]

I'm not so sure the difference in amp draw between fans is all that different; I'm guessing the main reason for the larger alternator is to keep up with any potential electrical draw from your trailered vehicle.

about 40% more...20 amps.....but yeah trailer electrical load too.

 

[Killroy Was Here]

I'm not so sure the difference in amp draw between fans is all that different; I'm guessing the main reason for the larger alternator is to keep up with any potential electrical draw from your trailered vehicle.

WATTS divided by VOLTS = AMPS
So definitely is a difference.

 

[JRobes]

WATTS divided by VOLTS = AMPS
So definitely is a difference.

(Edited numbers) Right, so since it's a 250 W difference between the 850 and 600 W fans. At 14 volts its 61 amps vs 43 amps (18 amps difference).

 

[ecidiego]

Right, so since it's a 150 W difference between the 800 and 650 W fans. At 14 volts its 57 amps vs 46 amps (only 11 amps difference).

It's 850 versus 600.

 

[JRobes]

It's 850 versus 600.

That's what I get for typing from my phone ?. Will amend my post above haha.

I am curious though, does anyone know how many amps the hitch wiring allows to a trailer?

 

[ecidiego]

That's what I get for typing from my phone

Your math lines up with the typo tho haha....

@ 14v:

850w - 60.7a
600w - 42.9a

 

[ShadowsPapa]

Have we seen this verified on door stickers? I can't verify as I have an Auto Mojave and they're all rated the same without or without factory tow.

@ShadowsPapa if you use the factory receiver hitch, aren't you rated same as a "factory" tow package according to your trim and transmission? I know you can't "make a Max Tow" later - but the regular tow package. I've not seen the tow rating broken out on "with or without tow package" - only trim and transmission.

I'd bet on different springs - which can be dealt with via air bags, etc.
Like you have pointed out already - fan, alternator, trailer hitch zoom, their receiver which bolts perfectly to the frame and bumper.....

 

[ShadowsPapa]

That's what I get for typing from my phone ?. Will amend my post above haha.

I am curious though, does anyone know how many amps the hitch wiring allows to a trailer?

That hot lead is fused at 30 I believe.

 

[JRobes]

Your math lines up with the typo tho haha....

@ 14v:

850w - 60.7a
600w - 42.9a

Huh? I put 61 vs 43? Rounding is allowed. Are you typing from your phone too ??? ?

Edit: I think you missed my post that I flipped the numbers (I had originally put 800 vs 650, but was incorrect and changed them to 850 and 600. But the actual math based off those numbers was still right... ?)

 

[ecidiego]

Huh? I put 61 vs 43? Rounding is allowed. Are you typing from your phone too ??? ?

No, you...

Ok Im leaving work, lol. What a thread!

 

[ShadowsPapa]

I'm not so sure the difference in amp draw between fans is all that different; I'm guessing the main reason for the larger alternator is to keep up with any potential electrical draw from your trailered vehicle.

Chris already caught it but yes, it's a much larger draw and at least the early JTs even had different high current fuses because of it.
You have to account for trailer draw, fan/cooling and so on.

These were problematic as far as cooling for towing ratings, so if towing, especially in heat or high altitude, you want the larger fan and alternator and make sure the high current fuse is for the larger draw fan.

Tow ratings are not a legal number it's just a (recently) standardized test to allow for apples to apples comparison.

True - unless you are in an accident. You can get tangled in civil court, etc. There's a whole lot of stuff out there on attorney's sites about this - they warn to be careful.
You can't be pulled over and ticketed, etc. - but if you run into trouble, someone will look for fault.

Not sure why we always get max tow into these when the vehicle is not a Sport/Sport S, etc. so nothing with max tow will apply and only serves to confuse others.

 

[ShadowsPapa]

So this one I’m looking at has a class 2 hitch rated at 3500 lbs but I have seen where Mojave with no max tow is 4500. Class 4 is rated for 10,000lbs but I think the Mojave with tow package can tow 6500lbs. Seems like this is sadly a no go

There is no "max tow" for Mojave. Just tow package. You are limited to what the chart in the OWNERS MANUAL says, regardless of your hitch. It's the truck, not the hitch.

Any modifications to a truck lower tow ratings - lifts, larger tires, etc. - they result in more power consumption from the engine, more heat generated, longer braking distances and so on.

Heat rejection is a big factor in these little trucks. The factory pairs things not by guessing or pulling out short straws or flipping a coin.
It's about a combination of parts working together as a system. In our case, engine speed vs engine load (torque, etc.) and so on down the line.
They have tires matched with gears matched with ....................

If you can't live with towing well under the factory tow ratings, sticking within payload limits, and have plans for mods that will impact those ratings greatly, buy a different truck, IMO.

Sponsored