Alternator Compatibility (and availability)

[Apples]

I apologize about Alternator Parts. Their web site information is a bot sketchy.

The Aura Systems is a bit sketchy too, but they assure me that make a system for the 2019+ model Ranger.

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[ctechbob]

Regarding my interest in a higher amperage alternator, I figure why not. If it doesn't hurt anything, the higher output would offer some flexibility for accessories TBD.

Yes and no.

Usually the higher the output of the alternator, the worse it is in low-speed charging. Alternators do not output their maximum until they are spinning in the 3-4000rpm range (Shaft RPM, not engine). Lower than that, their output tails off considerably. It is entirely possible that a higher output unit has LESS output at normal cruising engine speeds. Especially with our 10 speeds that keep the engines spinning slower.

That being the case, at slower speeds and less output, the voltage regulator will be pumping as much current as possible into the field windings to attempt to get the output up...end result of that is, more heat. More heat and slower spinning and you have a recipe for a shorter life.

Now, this all depends on the specific alternator, what I said above is more of a generalization of how they work and that bigger isn't always better.

 

[Dgc333]

I don't know about the 3 to 4000rpm for full output. Every alternator I have seen is rated for full output at 2000 rpm and every service manual I have seen tells you to test it at 2000 rpm.

 

[Frenchy]

I don't know about the 3 to 4000rpm for full output. Every alternator I have seen is rated for full output at 2000 rpm and every service manual I have seen tells you to test it at 2000 rpm.

One again he is talking RPM for the alternator. When engine RPM is 2000 the alternator is usually between 4000 to 6000 RPM's due to pulley diamiter. Make a bit more sense?

 

[Dgc333]

One again he is talking RPM for the alternator. When engine RPM is 2000 the alternator is usually between 4000 to 6000 RPM's due to pulley diamiter. Make a bit more sense?

I missed the part where he said shaft rpm. So basically a very small percentage of the time the engine is running the alternator will be spinning in it's most efficient rpm range.

 

[Frenchy]

I missed the part where he said shaft rpm. So basically a very small percentage of the time the engine is running the alternator will be spinning in it's most efficient rpm range.

Generally speaking yes. At idle most of the time an alternator isnt able to produce enough or full amperage but as long as there arent as many loads on you should be good.

 

[ctechbob]

Sortof an amusing story from back in the day about alternators.

Way back before Mitek Group (MTX Audio) purchased StreetWires from my former boss, we had an aftermarket alternator program. The alternators were built by a firm in TX to our specs. They included a few different models, but one thing in common with them all was that we installed the smallest pulley on them that we could fit on there (2" in that case), in an attempt to get them spinning faster and make up for their poor low-end (idle) performance.

Everything was great until GM decided to up the crankshaft pulley size on their trucks and fullsize SUV's. All of a sudden we (And by we, I mean our customers) started blowing up alternators, physically shredding parts from them. Normally it was the cooling fan, which on the models we had was an external unit. I used to have a picture somewhere of a brand new Suburban with a fan blade sticking out of its hood.

Wasn't long before we went from a 2" pulley to a 3" on the GM units we were shipping out. Problem solved, no more punctured hoods.

Moral of the story is, you can't just spin them faster, eventually parts start flying. I forget what the actual ratio was on those trucks, or how fast the alternator was spinning at redline. The number 20,000 is sticking in my head, but its been 20 years since I was in charge of that department, so memory is a little foggy.

 

[Mustang2Ranger]

I bought a set of belts for my Ranger the day I picked it up for the same reason

Cheap insurance as part for my off-road kit

Would be cool to have a spare alternator too

 

[MountainGoat]

Past a certain point it really makes more sense to tow an extra vehicle with you everywhere. That way if you break down you just switch out and tow the other vehicle then.

 

[103]

Old thread, but I always have a spare alternator and belts on any off-roading trip now. I wish someone made a relocation bracket.

 

[JesseS]

I keep hearing this.


There really isn't any such thing as a sealed, or watertight alternator.

A relocation kit, if it's possible to fit elsewhere, would be more likely.

The Toyota Land Cruiser has a sealed alternator with a closed air cooling system on some spec models. Someone posted a photo of it in another thread.

 

[D Fresh]

The Toyota Land Cruiser has a sealed alternator with a closed air cooling system on some spec models. Someone posted a photo of it in another thread.

And there are water cooled alternators available in Australia as well. But they cost buku bucks. Like 10 times the amount of a factory one.

If and when they ever make it here they'll be cost prohibitive. For as little water as my truck sees it seems smarter to simply stock a spare.

 

[JesseS]

And there are water cooled alternators available in Australia as well. But they cost buku bucks. Like 10 times the amount of a factory one.

If and when they ever make it here they'll be cost prohibitive. For as little water as my truck sees it seems smarter to simply stock a spare.

I hear you, but $300+ for a 'too deep' water crossing is steep, but so is $500-$700 for a back country haul out. I have seen many a 2-3' looking water crossing with a 6' deep low water channel in the middle. I try to avoid water.....

 

[Brett Fields]

I hear you, but $300+ for a 'too deep' water crossing is steep, but so is $500-$700 for a back country haul out. I have seen many a 2-3' looking water crossing with a 6' deep low water channel in the middle. I try to avoid water.....

Gotta say....
There's nothing about a pool of water that makes me wanna say "Hey, I'd really like to drive through that!" All things considered though, I'd also really hate to wait days to get an alternator after I do.

 

[Brett Fields]

Yes and no.

Usually the higher the output of the alternator, the worse it is in low-speed charging. Alternators do not output their maximum until they are spinning in the 3-4000rpm range (Shaft RPM, not engine). Lower than that, their output tails off considerably. It is entirely possible that a higher output unit has LESS output at normal cruising engine speeds. Especially with our 10 speeds that keep the engines spinning slower.

That being the case, at slower speeds and less output, the voltage regulator will be pumping as much current as possible into the field windings to attempt to get the output up...end result of that is, more heat. More heat and slower spinning and you have a recipe for a shorter life.

Now, this all depends on the specific alternator, what I said above is more of a generalization of how they work and that bigger isn't always better.

Remember though,
I'm talking about the stock Tremor alternator. Not some huge aftermarket part....

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