High Amp Alternator

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custodian

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I have a 2002 Chevy 2500HD 6.0 4X4 that I tow a 35' travel trailer. The travel trailer has two deep RV batteries that are charged while driving, also I run two 12v refrigerators while towing.

Now my question. Would I benifit to install a 255amp alternator on my truck? it currently has the 105amp, the one that's been on it since I bought the truck new.
 

squaredeal91

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I don't think you can over Amp because it means it won't have to work as hard? Maybe even get better fuel mileage lol. And didn't know they made one that high of Amp. Good to know!
 

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If the original is doing the job, I would stick with that size. Do you think the existing wiring in your truck can handle over double the load? That would be my concern.
My F550 has an OE 240A alternator in it, but it is also wired to handle it.
 

Camar068

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If you've significantly added more battery/load to stock, than what was currently working, then yes increase.
 

Ricko1966

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I have a 2002 Chevy 2500HD 6.0 4X4 that I tow a 35' travel trailer. The travel trailer has two deep RV batteries that are charged while driving, also I run two 12v refrigerators while towing.

Now my question. Would I benifit to install a 255amp alternator on my truck? it currently has the 105amp, the one that's been on it since I bought the truck new.
If it's working ,don't fix it. If and when your current alternator gives up then you might consider upgrading but having a 12 million amp alternator and 16 gauge wire is pointless.
 

Frankenchevy

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As mentioned, any wire between the alternator and house batteries should be sized accordingly. I’m installing a 370amp mech man alt on another truck with dual start batteries in the truck and dual 230ah LiFePo batteries in the camper right now. There’s quite a bit of 3/0 on that project.
 

PrairieDrifter

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I've gone with 2/0 everywhere with my 170 amp Mechman. This is for my square though.
 

Ellie Niner

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@custodian - Is the 105 amp alternator (I'm presuming it's a CS130D) unable to keep up with demand when you've got the travel trailer connected? While I'd prefer to not work an alternator near 100% capacity for long periods of time, sometimes it's better than installing a high amperage aftermarket alternator that uses the same size case as the original one. While the numbers look good, the reality is that cramming 200 amps worth of sh¡t in a 100 amp box often leads to a quick failure if you're going to be leaning hard on it for long periods of time. The earlier Delco CS130 (used in most GMT 400's) had a hard time dissipating enough heat to keep the rectifier from burning the grease out of the rear bearing in stock 100-105 amp form. Adding more capacity without increasing the cooling capability made these alternators die quickly in applications that needed a lot of output for more than a few minutes.

The later CS130D made a lot of changes, including mounting the rectifier outside the case; they're pretty stout and reliable. Still, it has a fairly small case, so I'm not sure what kind of output the design can reliably handle. I'd let it be if your current setup is working well. If you really need the extra amperage, step up to a larger frame size alternator and beefier wiring.
 

custodian

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If it's working ,don't fix it. If and when your current alternator gives up then you might consider upgrading but having a 12 million amp alternator and 16 gauge wire is pointless.
Working like it should, was just wondering if a higher amp alternaor was worth it.
 

custodian

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@custodian - Is the 105 amp alternator (I'm presuming it's a CS130D) unable to keep up with demand when you've got the travel trailer connected? While I'd prefer to not work an alternator near 100% capacity for long periods of time, sometimes it's better than installing a high amperage aftermarket alternator that uses the same size case as the original one. While the numbers look good, the reality is that cramming 200 amps worth of sh¡t in a 100 amp box often leads to a quick failure if you're going to be leaning hard on it for long periods of time. The earlier Delco CS130 (used in most GMT 400's) had a hard time dissipating enough heat to keep the rectifier from burning the grease out of the rear bearing in stock 100-105 amp form. Adding more capacity without increasing the cooling capability made these alternators die quickly in applications that needed a lot of output for more than a few minutes.

The later CS130D made a lot of changes, including mounting the rectifier outside the case; they're pretty stout and reliable. Still, it has a fairly small case, so I'm not sure what kind of output the design can reliably handle. I'd let it be if your current setup is working well. If you really need the extra amperage, step up to a larger frame size alternator and beefier wiring.
It's working like it should. Was just a thought about changing to a higher amp alternator.
 

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