Configure Alternator for 2500 tow

[Rockcrawlindude]

I only halfway read this thread but definitely buy the 4x4

 

[erik53]

Another reason to choose gas over diesel: Outside of camping, I only drive about 5,000 miles per year. This year we did about 3000 miles with our small camping trailer. With the new trailer we might go a little more, but total miles per year on the new truck will still be less than most people put on their vehicles. It is then hard to benefit from the fuel mileage and the durability of a diesel. The extra gas cost from upgrading to the 4.10 ratio is not going to be very important, and seems to give me great flexibility is choosing a trailer. However, I don't like engine noise. In my 2014 1500 with the 3.6 L, I like cruising along almost silently at about 1200 RPM. I wonder if the 6.4 with 4.10 would seem noisy in comparison.

 

[Brutal_HO]

Another reason to choose gas over diesel: Outside of camping, I only drive about 5,000 miles per year. This year we did about 3000 miles with our small camping trailer. With the new trailer we might go a little more, but total miles per year on the new truck will still be less than most people put on their vehicles. It is then hard to benefit from the fuel mileage and the durability of a diesel. The extra gas cost from upgrading to the 4.10 ratio is not going to be very important, and seems to give me great flexibility is choosing a trailer. However, I don't like engine noise. In my 2014 1500 with the 3.6 L, I like cruising along almost silently at about 1200 RPM. I wonder if the 6.4 with 4.10 would seem noisy in comparison.

The Hemi is going to be louder if you have to pull hills.

I pull 16K in the west and this is my 2nd diesel, not a daily driver, so it was a no brainer. I only put about 5K/year on it though it seems a tad more then first few years until the newness wears off. I bought mar 2020 and just rolled over 9200. Then again, my car has been unfun to drive for a while now too.

If I was pulling less, I'd likely as not run a gasser.

 

[el_barto]

Back to the original question: definitely order it with at least the 220amp or the dual (380amp). I installed the 220 in my truck (replacing the stock 180) but it’s not cheap if you pay MSRP; and retrofitting the duals is a much more challenging and expensive task.
The 220amp alternator is a better/more modern design (hairpin winding) than the 180amp, it produces way more amps at a lower rpm.

 

[Nick]

Right now I have 4x4 in the build. The reason is I am afraid of getting stuck on soggy ground when boondocking. Not into off-roading at this stage of my life, but certainly travel some dirt roads. But I am thinking of going 2x4 because: 1. The 4x4 sits so high off the ground, I could barely enter it during test drive (no running boards). I would get running boards, but fear the my wife and visiting grandkids would still find it difficult to get in. 2. The 2x4 should give me more load capacity, which is critical for towing a 5w. Towing capacity is not the limiting number for those. 3. I would save some $$ by omitting the 4x4. 4. When I had a 4x4 Chevy years ago, I saw significant extra maintenance costs from that. Not much concerned with snow, since I live in Phoenix, but of course one could run into snow and ice at a Colorado mountain pass.

Just make sure you get the limited slip option . about $475 for so .

 

[CdnHO]

Prepper motto: Two is one and one is none.

Glad I opted for the dual 220 (diesel option) on my truck even though I don't currently have any high amp charge requirements. The recovery after cold starts is so much quicker and the chance of anything being shut down due to low voltage lessened.

You sure couldn't buy that alternator for what they are charging for it as an option.

 

[erik53]

The 220 alternator is in my build. I think it is enough even if I add the equipment to charge the RV house batteries at high current. I can't think of any way I would use the 380 amps, but I understand some people might want it for a snow plow (?) or massive bank of lights.
All along I have had the DSA "Anti-Spin Differential Rear Axle" in the build. I think that is another name for limited slip.

 

[JohnandDonna]

Remember the old adage, better to have and not need than to need and not have. I ordered mine as well. No one seems to stock the 6.4 Hemi in anything other than the Tradesman trim. Dual alternators and the 4.10 limited slip rear end. For the guy who mentioned noise, the 4.10 does not make any more noise than the 3.73. What it does do is make towing easier. And when not towing the truck is very peppy off the line. I have towed in the Smokies and out west. The Hemi has plenty of power for my 9000 pound TT. Just be aware, it is a thirsty beast. But I knew that going in.

 

[Rockcrawlindude]

I went with the base 180-amp alternator. Suits my needs fine. Battery choice is more important, in my opinion.

No alternator option can keep up with a winch anyway at 440 amps max draw.

 

[erik53]

Gas mileage for daily driving with the 6.4 and 4.10 axle ratio is not a major concern, but the engine noise would probably be a little worse than with the 3.73. An idea just hit me. We are familiar how the Tow/hill function will change the shift points toward higher RPM's. Any reason why we could not have a Quiet/ECO button to move the shift point in the other direction, so that with that function activated, the vehicle with 4.10 would behave more like a 3.73 with the function not activated?

 

[Firebird]

Gas mileage for daily driving with the 6.4 and 4.10 axle ratio is not a major concern, but the engine noise would probably be a little worse than with the 3.73. An idea just hit me. We are familiar how the Tow/hill function will change the shift points toward higher RPM's. Any reason why we could not have a Quiet/ECO button to move the shift point in the other direction, so that with that function activated, the vehicle with 4.10 would behave more like a 3.73 with the function not activated?

My 4.10 geared 6.4 was no louder than my 3.73 truck

 

[Brutal_HO]

Remember the old adage, better to have and not need than to need and not have. I ordered mine as well. No one seems to stock the 6.4 Hemi in anything other than the Tradesman trim. Dual alternators and the 4.10 limited slip rear end. For the guy who mentioned noise, the 4.10 does not make any more noise than the 3.73. What it does do is make towing easier. And when not towing the truck is very peppy off the line. I have towed in the Smokies and out west. The Hemi has plenty of power for my 9000 pound TT. Just be aware, it is a thirsty beast. But I knew that going in.

Gas mileage for daily driving with the 6.4 and 4.10 axle ratio is not a major concern, but the engine noise would probably be a little worse than with the 3.73. An idea just hit me. We are familiar how the Tow/hill function will change the shift points toward higher RPM's. Any reason why we could not have a Quiet/ECO button to move the shift point in the other direction, so that with that function activated, the vehicle with 4.10 would behave more like a 3.73 with the function not activated?

My 4.10 geared 6.4 was no louder than my 3.73 truck

I didn't read that he was equating noise to the rear end, just the higher revving gasser vs the diesel.

 

[MEGA HO]

Get a 4x4 and if a power step is an option on your trim level, then get that too. My 3 y.o. can get into my 4x4 and climb into his seat. Power step comes down really low

 

[H3LZSN1P3R]

I went with the base 180-amp alternator. Suits my needs fine. Battery choice is more important, in my opinion.

No alternator option can keep up with a winch anyway at 440 amps max draw.

My dual 220s would put up a good fight lol

 

[H3LZSN1P3R]

Gas mileage for daily driving with the 6.4 and 4.10 axle ratio is not a major concern, but the engine noise would probably be a little worse than with the 3.73. An idea just hit me. We are familiar how the Tow/hill function will change the shift points toward higher RPM's. Any reason why we could not have a Quiet/ECO button to move the shift point in the other direction, so that with that function activated, the vehicle with 4.10 would behave more like a 3.73 with the function not activated?

Lugging the engine would take a toll on the engine life

 

[erik53]

My idea was that with the 4.10:1 axle ratio (which raises engine rpm) and shift points to lower engine rpm, the engine rpm would end up being the same as with 3.73:1 and standard shift points. I don't see why the engine would lug more at the same rpm when the transmission together with differential has the same overall ratio, just redistributed over the various components. Of course one could argue that the load and wear is also distributed in a new way, and friction/efficiency is affected.

 

[erik53]

While I don't drive a lot around town, so gas mileage without towing is not that important, I would be interested to learn what kind of mpg to expect with the 4.10 and no trailer. I am not a leadfoot. In fact, with my 1500 I have the gas mileage display on the screen all the time while driving, and trying to improve mpg. BTW, I find that the cruise control harms mpg, as it never upshifts at constant speed. Without cruise control, If I just lift the foot, I get the upshift and dramatically better mpg.

 

[CdnHO]

While I don't drive a lot around town, so gas mileage without towing is not that important, I would be interested to learn what kind of mpg to expect with the 4.10 and no trailer. I am not a leadfoot. In fact, with my 1500 I have the gas mileage display on the screen all the time while driving, and trying to improve mpg. BTW, I find that the cruise control harms mpg, as it never upshifts at constant speed. Without cruise control, If I just lift the foot, I get the upshift and dramatically better mpg.

I get around 16.6 to 17 calculated driving around with the average trip around 12 miles. Haven't had it out on a long highway run. HO dually with 4.10 axle and dual alternators.

 

[Firebird]

While I don't drive a lot around town, so gas mileage without towing is not that important, I would be interested to learn what kind of mpg to expect with the 4.10 and no trailer. I am not a leadfoot. In fact, with my 1500 I have the gas mileage display on the screen all the time while driving, and trying to improve mpg. BTW, I find that the cruise control harms mpg, as it never upshifts at constant speed. Without cruise control, If I just lift the foot, I get the upshift and dramatically better mpg.

4.10 with the 6.4? If so, then I always averaged 10.5 to 11.3 in town

 

[H3LZSN1P3R]

My idea was that with the 4.10:1 axle ratio (which raises engine rpm) and shift points to lower engine rpm, the engine rpm would end up being the same as with 3.73:1 and standard shift points. I don't see why the engine would lug more at the same rpm when the transmission together with differential has the same overall ratio, just redistributed over the various components. Of course one could argue that the load and wear is also distributed in a new way, and friction/efficiency is affected.

I think the only way to truly achieve what you are mentioning is have an extra overdrive in the trans… changing the shift points lower would not do it as the engine would be lugging if it shifted any lower the other Option would be a 2 speed transfercase (the old 2nd gens nv5600 with 4.10s you could get this aftermarket) could as the RPM reduction would have to happen after the transmission or by physically changing ratios in the trans