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How to Choose the Right Alternator for Your Application

Learn how to spec the correct alternator for your application.

Episode 302: Technology on commercial trucks continues to become more complex as more advanced electrical systems are developed. This is changing the demands on the charging system. Alternators need to be high-output and high-performance to meet the needs of the modern semi-truck.

Jonathan E. Smith is the Business Development Manager and Marketing Manager of Prestolite Electric. In this episode, we discuss how to choose the correct alternator for the application of your truck and avoid system-wide electrical issues and unnecessary downtime that occurs when you install the incorrect alternator.  


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Transcript of Episode

Jamie Irvine:

You are listening to The Heavy Duty Parts Report. I’m your host, Jamie Irvine, and this is the place where we have conversations that empower heavy-duty people.

Welcome to another episode of The Heavy Duty Parts Report. What are we going to talk about today? Well, in today’s episode, we’re going to talk about the impact the Fed are having when they raise interest rates, and this has had an impact on brick and mortar parts and service companies, heavy-duty companies in the industry.

We’re going to talk about what that impact is and what to do about it. We are going to learn about what we need to consider when specing replacement alternators for heavy-duty trucks and stick around to the end as we discuss how Murphy’s law impacts truckers and what to do about it. We could not do any of this without our sponsors. A big thank you to FindItParts.

If you haven’t already, go over to finditparts.com and check out their amazing platform. You can get parts quickly. It is a phenomenal opportunity for you to get access to any of the parts we talk about on The Heavy Duty Parts Report. Again, we couldn’t do this without their support, so a big thank you to Find It Parts.

So in this week’s feature interview, we’re going to discuss the changes to trucks, specifically the way electrification impacts how you spec replacement alternators. But before we get into that, that got me thinking about the many changes that we have seen over the last couple of years in the industry. One of the changes has been predominantly been fueled by the economy and by inflation.

And so just like when you’re servicing a heavy-duty truck, you have to adapt with the changes to the trucks. You have to adapt how you run your business with the changes in the world, in the economy and in the industry. Rapid inflation has prompted the Federal Reserve to raise interest rates effectively pulling cash off the street.

At the Heavy Duty Consulting Corporation we have seen the way that this move by the Federal Reserve has impacted heavy-duty companies. Banks are now calling in their loans and refinancing with the companies that they serve to take advantage of these higher interest rates.

This whole situation has made cash a lot more expensive, a lot more hard to get your hands on, and that has a direct implication on the cashflow of a business.

Now, we’ve seen some of our clients adapt to this and take advantage actually of this because it’s created some new opportunities, but unfortunately we’ve also seen a lot of heavy-duty companies being caught by this because they were over leveraged. In a worst case scenario, we’ve actually seen at least one heavy-duty company so far literally have to liquidate their inventory and are now going to be shutting down operations because they have to liquidate that inventory to pay back the loans to the bank.

This is a worst case scenario. We’re not seeing this happen widespread, but we are seeing a lot of companies have to use their cash reserves to pay back loans that have been called in, thereby constricting their ability to do things like buy inventory and invest in their business. So this is a real situation. It’s happening right now in ’23. It’s going to continue to happen in ’24.

I actually think we may see more businesses close, especially ones that are already leveraged, and right now we’re seeing this predominantly impact brick and mortar operations because of the high costs associated with that business model.

So just like when we’re servicing equipment, we need to adapt to the changing landscape. If you’re struggling right now, reach out to us and we will do all that we can to help you to develop a strategy to adapt your business and to not only survive some of these changes but actually be able to take advantage of them.

How would you do that? One is with inventory, if you have inventory, inventory is now king, and there are certain strategies that can be used if you have the ability to move a lot of inventory suppliers are interested and we can talk about that as well. So if you want to meet with us, just head over to heavydutyconsulting.com/meetwith-us. Links will be in the show notes.

We’d love to have an opportunity to talk to you. If you’re buying parts, make sure you go to finditparts.com and start using their service. We’ve got some episodes on the heavy-duty parts of it where we’ve interviewed them, we’ve talked about their business model. They can be an asset to you right now, one that you should be taking advantage of, and we will include in the show notes a link to those episodes with FindItParts.

It’s time now for our featured guest interview, and this week we’re going to replay an interview that I did last year with Jonathan E. Smith, business Development Manager at Prestolite. In this interview, we talk about the need to change how we spec alternators now that trucks have been electrified and the electrical system demand has exponentially increased.

Listen into my interview with Jonathan E. Smith, Business Development Manager at Prestolite. And when I think about commercial trucks, especially over let’s say the last 10 years, the electrical system demands has just gone up and up and up and up. I think back to the trucks that we used to remanufacture pneumatic controls for and everything was mechanical. Everything was just basically either mechanical or air, very little electrical.

Now that has all changed, so I’m very happy to have my guest, Jonathan Smith. He’s the business development manager and marketing manager of Prestolite Electric, and Jonathan is back on the show, a returning guest. Jonathan, welcome back to The Heavy Duty Parts Report. So glad to have you here.

Jonathan Smith:

Yeah, nice to be here.

Jamie Irvine:

Good to talk to you again. So we’re going to talk a little bit about the way that things have changed with commercial trucks. So just talk to us a little bit about the overarching trends with commercial trucks and then we’ll get into some specifics.

Jonathan Smith:

Okay, yeah, and what we’ve seen over the last few years, and kind of alluded to it in your introduction was the ever-increasing amperage loads on commercial vehicles, whether in the seventies it was going from an AM radio to an FM radio and a CB. Now we have navigation systems, ABS and systems. You have the telematics on vehicle troubleshooting where the vehicle’s going down the road and…

Jamie Irvine:

Your favorite podcast app.

Jonathan Smith:

Yeah. Yes, actually my favorite podcast app. But yeah, all those things, even though like each one, if you look at the amperage requirement for those aren’t a lot, but you add ’em all up and it creates significantly more amperage demands on the vehicle, and then you couple that with the battery to HVAC systems.

We’ve had no idling for a long time, but that’s just as we get into zero emissions and things like that, that’s only going to increase. So the larger the alternator you have, the better performance you’re going to get out of your battery to HVAC system.

And then voltage has gone up as well. We’re still North America, we’re 12 volt, but we’re seeing 24 volt, 36 volt. Those are going to increase as these demands increase and you step more toward either hybrid or E drive. There is talk of plugin hybrid, but I think the infrastructure for plugins is a little far away, but it’s out there. We’ll definitely see it in years of my lifetime.

Jamie Irvine:

Yeah, and that’s the thing, when you think about commercial trucks, I think of just the number of computers on a given truck, right? If I remember correctly, there’s one ECM dedicated I think just to the seat in, I think it’s the Volvo application. Don’t quote me on that, but I remember someone saying something along those lines. It was one of the major trucks, and they have a whole ECM just dedicated to controlling the seat.

Things have gotten complicated. The electrical systems, there’s so much more demand. Is it just responding to new technology or is there any other underlying drivers when I think of as truck OEMs are trying to get more performance out of the vehicle as well?

Jonathan Smith:

Yes. Yeah, and when you’re talking about higher voltages and stuff, the higher voltage requires less wire. You don’t have to have as big a wire as you do with a 12 volt. So that significantly increases the performance of the vehicle, the higher amperage loads, as you get more of these electrical loads on there, the higher amperage make sure that everything runs at an optimal level, and I was going to get a little bit into that later, but yeah, you don’t want things to run at low voltage.

So you have a 12 volt system, you want to make sure your batteries are at 12 volts. All that stuff runs optimally. So once you start having too many loads without enough alternator to cover those, then that starts taking drain out of your battery.

And once that starts happening, you’re running at 10 volts, 11 volts, and those components really don’t like that. They don’t run well at that and they don’t last long with that. Even your starter when you start doing low voltage cranks on your starter over and over and over, the life of that starter significantly decreases.

Jamie Irvine:

Right and then, this is where total cost of operation becomes a real factor, because if we start to run in, let’s just say not an optimal way, we start to have failures. Now we’re driving up our costs, and it all started just with the extra load on the electrical system.

Jonathan Smith:

Absolutely a hundred percent total cost of ownership, keeping that vehicle on the road. So some of the alternators that we’ll talk about in a little bit upfront, they’re not the cheapest alternator, but your total cost of ownership, where we’re offering a four year unlimited mileage warranty on these products that’s designed to keep you on the road trouble free for four years. So you’re not worrying about that.

So if you have a lesser alternator or one that doesn’t perform as well and you start changing out starters, a starter change out, that’s an hour of labor. How much is an hour of labor nowadays? A hundred dollars an hour, $150 an hour, you have three alternators put on over the four year period that this one would’ve lasted you.

Again, there’s $500 in labor just on changing out alternators. So really, really those things significantly increase over time where you spend the money upfront, you get the value out of it on the other side.

Jamie Irvine:

And just throw in there a pandemic and global geopolitical issues messing up the supply chain. And you might get caught where one of the parts you need isn’t available and now your downtime goes through the roof. Okay, so we’re going to talk some more specific products when we get back from the break. We’ll be right back.

Commercial Break:

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Jamie Irvine:

As we all know, there’s so many more electrical demands with each commercial truck and each year that they come out, it seems to be more and more so that means you’ve got to adapt your approach to things like your alternators and your starters.

So Jonathan, what is your recommendation to someone who is saying, look, I need to spec the right alternator, the right starter for the system on my truck and the demands it’s going to go through. First of all, let’s talk about how they would come to the correct part and then we’ll talk about some specific products that your company sells.

Jonathan Smith:

Okay yeah. When you’re ordering a new truck, now with Navistar, we’re first fit with Navistar. As you add electrical loads to your option sheet, they have it sort of automatically increases the size of your alternator, your requirement of your alternator goes up as you’ve added things. And then we also have on the other side, we have a technical service bulletin that you could go through.

So you had an older truck and you were either unsure of the performance of your alternator, maybe you’ve gone through more than you thought you should have, or you’ve added more electrical loads, you’ve added the telematics, they’ve added HVAC system.

You’re not getting the performance out of that that you think you should. We have a tech service bulletin that’ll go through step-by-step on how to calculate your vehicle’s load, and then we take that calculation, go to our power curve.

You want to make sure you’re covering all your loads at idle. So you have 150 amp load, 150, 160. That doesn’t sound like a ton, but that’s at idle. A 250 amp. alternator probably doesn’t put out most of ’em don’t put out 150 amps at idle. So our 350 amp alternator puts out 200, 210 amps at idle, but that’s how you kind of calculate it. You want to see what your vehicle load is, and then you want to compensate for the thermal degradation, you want to leave a little bit to go back to the batteries.

So you’re 10% for thermal degradation because any alternator, I don’t care whose it is, once that alternator starts getting warm or any electrical motor like that gets warm, it loses efficiency. At 70 degrees, it puts out it’s 4,000 RPM, it’s putting out 250 amps, well at 125 degrees C, it’s putting out less than that at the same amperage and it’s mine, yours, whoever makes those. But you want to make sure that you can compensate for that temperature as well.

The under hood temperatures have gone up as well as the amperatures have gone up and they’ll continue to go up because as you get aerodynamics, you don’t want air coming into the motor, you want it going around, you want it going underneath. So the under hood engine temperatures have gone up significantly as well. So all of our products that we have ’em at 125 degrees C, even our 420 amp IdlePro Extreme alternator is rated at 125 degrees C.

Jamie Irvine:

Okay. Let’s talk about IdlePro because that’s a line that your company has brought out. It’s specifically for that user that needs that next level technology. So let’s talk a little bit about it. What is IdlePro? What makes it perform the way it does?

Jonathan Smith:

Yep. We have our IdlePro alternators. They are high amperage dual fan alternators. They’re e coated for corrosion resistance. We are first fit on Navistar with 160 amp version, and then on Thomas bus, Bluebird bus, we’re a 210 amp version. We also have a 240 amp version that has about 160, 170 amps at idle. The 210 and the 240 are covered by our Prestolite Power Promise warranty.

So on a brush unit, we’re giving a three year unlimited mileage warranty. And then when you step up to brushless units, we have our IdlePro Extreme alternators, and they’re a 220 amp up to 420 amp brushless, high amp brushless units for corrosion resistance. They have the remote sense, the lamp driver, and we use bar wound staters so that they have significantly more output at idle. So even the 220 amp has over 200 amps at idle.

Jamie Irvine:

So it sounds like a lot of engineering went into this IdlePro line, and it really comes down to matching the part to the application. So let’s talk a little bit about economic impact. You alluded to this before in our previous segment, but when you have something that has a higher purchase price, like the IdlePro line, does it actually cost more?

Jonathan Smith:

No. I mean, and that’s the thing. You get to a 350 amp alternator, so you’ve gone out and you’ve bought your truck, and then you put on a battery HVAC system, and then we give you the bill or you get the bill for the 350 amp alternator. I can get a 200 amp for a third of that or half of that. So what are the things that are really important in the market today?

Keeping your vehicle on the road and driver retention, right, because it is hard to get drivers. So you’ve cheaped out on the alternator, you put a 200 amp alternator on this battery to HVAC system, your driver goes out, he drives eight hours down the road, he stops at night, and this system is designed to give eight to 10 hours of creature comforts .

Jamie Irvine:

Ready, he gets his chimichanga, puts it in the microwave boom, no power.

Jonathan Smith:

Absolutely. Yeah. So instead he gets there instead of having eight to 10 hours and three hours in, he’s hot, he’s cold, his chimichanga is cold.

Jamie Irvine:

He’s in the middle of emailing or Face Timing with his wife, and the system goes down and his tablet that’s charging dies. I mean, now the guy, he’s mad.

Jonathan Smith:

He’s mad. And the other thing we alluded to earlier was low voltage. So you’ve got all these components that are low voltage, you’re not covering your loads as you go down the road. You didn’t put a big enough alternator on, so any of your sensitive electrical components, your switches, sensors, all that stuff, your seats, the ECM that just controls your seat, low voltage to that can burn out that component.

So how many of those things do you go through when you saved X amount of dollars, you went for a third of the price alternator, but you’ve gone through significant electrical components, one road stop, one breakdown on the side of the road for any one of these, wipes out the difference in money you saved on that one alternator before you even go and change that alternator and put the right one on.

So total cost of ownership, put on our 350 amp IdlePro Extreme alternator, and you get the battery to HVC you need, and you have four years of limited mileage warranty on that. All your electrical components are covered, your batteries are cycling optimally. Paying out a little bit more on the front end really gets you a lot of benefit on the other side.

Jamie Irvine:

Right, and I mean even if you were just to pick one of the more easily measured economic parts of this equation, so okay, I spend three times as much buying the part, but it lasts for four years instead of two. Right?

Well, and all of a sudden that bill to have it changed and the labor and the additional downtime, proper decision around purchase price is now making you money two years out. If it fails a third time, well now you’re into actually really driving down lower total cost of operation. And then there’s all of those other components.

How much does it cost when if you’re not running a fleet in the way that you should and there’s constant breakdowns and you’re losing drivers because of it, what is the cost of hiring and training a driver? It’s in the thousands. So sometimes it’s a little bit of a leap for people to say, yeah, well what I choose on spec for alternators isn’t going to affect driver retention.

I mean, how are you correlating those two? Maybe it’s not a direct correlation, but it’s certainly part of the equation. And so a percentage of the cost of retention and hiring and training would have to be allocated to the total decisions you make as a fleet on parts.

And when I was selling parts, Jonathan, and maybe you can speak to this because you do a lot of work with fleets and training and things like that through your distribution network, but when I was selling parts, I kind of found that if the fleet had a culture around lower total cost of operation, they bought higher quality parts and that seemed to infiltrate like every aspect of the way they did business.

Conversely, if they’re not, it has negative implications across the board on the way they run their business. Is that what you’ve seen as well?

Jonathan Smith:

I’ve seen that and I’ve seen even simpler. If I’ve gone to a fleet and I’ve gone to a fleet with an outside guy and we walk in the door and I’m tripping over cores here and I’m skin my pant leg on a brake drum that’s greasy and I come out…

Jamie Irvine:

You get that one dot of axle grease and then all of a sudden it’s all over your shirt. You’re like, how did that happen?

Jonathan Smith:

Yeah, I mean, I’m head to toe.

Jamie Irvine:

Yeah, yeah. It’s in your hair.

Jonathan Smith:

Hair I have left. But yeah, those kinds of things, simple, simple things, a clean, I can walk in and if I know somebody’s going to say, Hey, I’m having problems, I can walk in there and know if they’re having problems or not. Simplest thing on a vehicle is keep your batteries clean.

That keeps the discharge down on the batteries because the batteries are discharging, the truck’s got to work harder to keep those charged during the day. So yeah, that starts with keeping things clean, keeping your vehicles clean, and then looking at beyond the cost of the part here as what it’s going to get you all the way across.

Jamie Irvine:

Hey, Jonathan, can you think of any occasion where a fleet made this change with the IdlePro product line and then they got some significant improvements? I know you’ve been selling this now for a little over a year or a couple years now. Can you think of any specific stories where fleets were successful? I think sometimes we can talk about the idea, but then if we show them an example, it helps people to conceptualize it.

Jonathan Smith:

And we have a significant national fleet that we’ve been working with because on these alternators, you just don’t go to DT&A and say, hey, put this in your option book. We have to go through a five season tests in order to get the alternator qualified to even and DT&A, I mean, they’re very strict as far as what they’ll allow you to put on. Even a big fleet says, hey, I want to put this alternator on my truck. Well, until it passes the five season test, we’re not going to do it, and I don’t care how many trucks you want to order.

So we had a large fleet that we had some not as much success with, and probably 25 years ago we went back in there with this alternator and they put it on versus the competitor’s product and performance at idle, performance over the road with the e-coating and the high temperature rating. We were not only allowed us to pass our five season test, but they’re going to be specing our alternator on those vehicles as opposed to the competitor’s product.

Jamie Irvine:

That makes a lot of sense. The five seasons, so that’s literally, it has to be, what, 15 months, right? I was just thinking you might be able to get lucky on one season, maybe on two, but not on all four plus an extra winter, the performance in the lab versus the performance in the field, and that’s where it’s got to pass the mustard.

It’s got to be something that operates in real world conditions across that, like you say, that large range of temperature, all of those conditions, and you have to be able to repeat that success season after season. So that’s cool. I didn’t know that they actually called it a five season test.

Jonathan Smith:

Yeah, yeah. We’re very well versed in the five season test.

Jamie Irvine:

Yeah, you’ve gotten your PhD at that. As heavy-duty equipment becomes more electrified and more complex, we will need to update the way that we spec, diagnose, buy replacement parts and repair these trucks and pieces of heavy-duty equipment.

I think today’s episode is a good example of that where some of the old ways of thinking we need to change, we need to keep up to date with the new systems and the new demands of modern day equipment. And that being adaptable I think is part of being heavy-duty, right? It’s not just about being resilient, it’s also about quickly adapting and overcoming any challenges that we face.

So I think today’s episode was a great example of that. I hope you enjoyed it. It’s time for That’s Not Heavy Duty. Have you ever heard of Murphy’s Law? Well, Murphy’s Law is basically everything that can go wrong will go wrong.

Don’t ignore doing inspections and doing preventative maintenance – That’s Not Heavy Duty. @Definitely_riley on TikTok, they made a funny video that I think really highlights the all too common situation faced by truckers. Now, this video doesn’t have any audio, but let me describe exactly what is on the video. First of all, in the video, he plays the Genesis song, That’s All.

And the caption on the video says, ‘Your alternator falls off 300 miles after you plug 20 holes in the rad’. It’s exactly the kind of Murphy’s Law that happens. And I remember selling parts. I would sell parts to someone, we would get a truck up and running, and then yeah, they would phone me not that long later and say, you can’t believe it, now this failed. I need help. And so this is just all too common in the trucking industry. Some of it is unavoidable, but a lot of it is avoidable.

And thank you very much to @definitely_riley for being heavy-duty and reminding us of the importance of doing regular maintenance and avoiding downtime as much as possible. Thank you so much for listening to this week’s episode. We are attending HDAW, the Heavy-Duty Aftermarket Week this week, and we’re so excited.

The whole team is heading to Grapevine, Texas. Diana Cudmore, our Podcast Director will be there. Scott Boltz, our Director of Consulting Services, and Mike Parnitzke, one of our consultants along with yours truly will be at the show.

So if you are there right now and you’ve been listening to today’s episode on let’s say Monday, make sure you come find us. Our booth is just outside the exhibition hall. We’ve got a podcast booth there. We are doing interviews on Tuesday and we are having meetings on Wednesday. So we are so looking forward to coming together as an industry to talk about heavy-duty parts. It’s what we do.

If you haven’t already and you want to listen to some of the interviews we do from the show floor, why not go over to heavydutypartsreport.com today and hit the follow button. You get one weekly email with all of our content so you never miss out. And if you enjoy listening to the show and the podcast player of your choice, hit follow button. And if you like watching on YouTube, make sure you subscribe.

We would really appreciate that. Also, go check out our sponsor, finditparts.com. We couldn’t do what we do without support from great sponsors like FindItParts. So go over to finditparts.com today if you buy parts. And don’t forget, Be Heavy Duty.

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