GPS Tune-Up Kit Review: Worth It for Your Onan KY 4000?
First Impressions
Ever been stranded with a dead RV generator just when you needed it most? I have, and let me tell you, it’s not fun. That’s why I decided to take preventative maintenance seriously and try the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for my Cummins Onan RV Generator. I’d been putting it off for too long, and a cross-country trip was looming!
When the kit arrived, I was immediately impressed. The packaging was sturdy, and everything felt well-made. The inclusion of the ONAMAX 10W30 oil was a thoughtful touch. My initial impression was that this wasn’t some generic collection of parts. It was a quality kit, specifically designed for my generator. After installing the GPS GENERATOR PARTS SPECIALIST kit, my generator started smoother and ran quieter than it had in years! Keep reading, because I’m about to dive into the details of this tune-up kit and share my experience step-by-step.

Key Features & Specifications
Alright, let’s dive into the features of the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil for use with Spec P – R. As someone who relies on my RV generator, especially during those off-grid adventures, a reliable tune-up kit is essential. I’ve put this kit through its paces, and here’s my take on its key features.
All-Inclusive Onan OEM Parts
This GPS GENERATOR PARTS SPECIALIST Tune Up Kit stands out because it includes all the necessary Onan OEM (Original Equipment Manufacturer) hard parts required for a complete generator maintenance session. This means you get the exact Onan parts designed specifically for your Cummins Onan RV Generator Model KY 4000. No guesswork, no compatibility issues, just the right parts for the job. You get the peace of mind knowing that every component – from the oil to the spark plug – is made to the exact specifications needed for peak performance.
Why does this matter? Using OEM parts means you maintain the generator’s original performance and reliability. I’ve learned the hard way that aftermarket parts can sometimes fall short, leading to decreased efficiency and potential damage in the long run. With the GPS GENERATOR PARTS SPECIALIST kit, you avoid those risks and protect your investment. In my experience, since using this kit, my generator runs smoother, quieter, and starts much easier, especially in colder weather.
Genuine Onan ONAMAX 10W30 Oil
The inclusion of two quarts of Onan ONAMAX 10W30 oil (PN: A063E183) is a major plus. This isn’t just any oil; it’s formulated specifically for Onan generators. Onan knows their engines best, and this oil is designed to provide optimal lubrication and protection under the demanding conditions that RV generators often face. I’ve always made it a point to use the recommended oil, and I’ve noticed a significant difference in engine wear over the years.
What’s so important about using the right oil? The correct oil ensures proper cooling and lubrication of the engine’s internal components, extending the generator’s lifespan and reducing the risk of breakdowns. I once used a generic oil in a pinch, and the generator ran noticeably hotter and rougher. With the ONAMAX oil provided in this GPS GENERATOR PARTS SPECIALIST Tune Up Kit, I have confidence that my generator is getting the protection it needs. I recently went on a boondocking trip in the desert, and even with the extreme heat, the generator ran like a champ, thanks in part to the quality of this oil.
Onan Spark Plug and Gap Tool
This GPS GENERATOR PARTS SPECIALIST Tune Up Kit contains the correct Onan spark plug (PN: 167-0275) AND the GPS Spark Plug Gap Tool (PN: 627-0560). The correct gap on a spark plug can make all the difference in the world. Spark plugs are key to starting and maintaining efficient combustion within the generator. Using the right spark plug ensures proper ignition, leading to easier starts, smoother operation, and better fuel efficiency. Over time, spark plugs wear out, leading to misfires and reduced performance. Replacing them with the correct Onan spark plug restores the generator’s optimal performance.
I’ve seen firsthand the difference a new spark plug can make. Before swapping it out with the Onan spark plug from this kit, my generator was struggling to start on the first try, especially in humid conditions. After the replacement, it fired up instantly, every single time. And using the gap tool helped make sure the gap was perfect. I also noticed a slight improvement in fuel economy during my last camping trip – a welcome bonus.
Air and Fuel Filtration
Proper filtration is crucial for maintaining the health and efficiency of any engine, and RV generators are no exception. The Onan Air Filter (PN: 140-3280) and Fuel Filter (PN: 149-2457) included in the GPS GENERATOR PARTS SPECIALIST Tune Up Kit are designed to keep contaminants out of the engine. The air filter prevents dust, dirt, and debris from entering the engine, while the fuel filter ensures that only clean fuel reaches the carburetor or fuel injectors. This translates to improved performance, reduced wear, and a longer lifespan for your generator.
What’s the real-world benefit? A clean air filter ensures that the engine receives the proper amount of air for combustion, maximizing fuel efficiency and power output. A clean fuel filter prevents clogs and ensures a steady flow of fuel, preventing stalling and rough running. I remember one trip where I neglected to change the fuel filter, and the generator started sputtering and eventually died in the middle of the night. I learned my lesson the hard way. Now, I make it a point to replace both filters regularly using the GPS GENERATOR PARTS SPECIALIST Tune Up Kit, and I haven’t had any issues since.

Who Should Buy This
Okay, let’s talk about the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil. I’ve seen this kit in action, and it’s not for everyone, but for certain RVers, it’s a lifesaver.
Who Should Buy This:
First, consider the weekend warrior RV enthusiast. I’m talking about folks who take their RV out maybe once or twice a month for a quick camping trip or to visit family. These folks don’t have a ton of time for maintenance; they want to get in, get out, and have a good time. Their pain point is usually convenience. They don’t want to spend hours tracking down the right parts at different stores. This GPS GENERATOR PARTS SPECIALIST Tune Up Kit is a one-stop shop. It includes everything they need – air filter, fuel filter, spark plug, and the correct ONAMAX 10W30 oil. I’ve seen these RVers struggle with mismatched parts before, leading to wasted time and a frustrating start to their vacation. With this kit, it’s all there, ready to go. You are getting the correct parts made for your generator every time. I like using it because I know I am not taking any chances.
Then, there’s the full-time RVer on a budget. These folks depend on their generators for power daily. Reliability is key, but they also need to be mindful of expenses. Regular maintenance is critical to extending the life of their Onan KY 4000 generator. I’ve met full-timers who skip tune-ups to save money, and that usually leads to bigger, more expensive problems down the road. The GPS GENERATOR PARTS SPECIALIST Tune Up Kit helps them stay on top of maintenance without breaking the bank. Buying the components individually can add up, plus you’re never quite sure if you’re getting the right spec. This kit provides peace of mind at a reasonable price. It gets them back to enjoying the open road and less time wrenching on their generator.
And, let’s not forget the boondocking enthusiast. These are the RVers who love to get off the grid and explore remote areas. They rely heavily on their generator for power, as solar might not always cut it. They need their Onan KY 4000 generator to be in top condition to handle the demands of off-grid living. A dirty air filter or old spark plug can cause the generator to run inefficiently or even fail completely, which is a disaster when you’re miles from civilization. I’ve seen it happen firsthand! The GPS GENERATOR PARTS SPECIALIST Tune Up Kit ensures their generator is running smoothly, so they can keep the lights on and the refrigerator cold while enjoying the solitude of the wilderness. If the parts in your generator are old, you aren’t getting the same efficiency as you would if you had newer parts. By maintaining your generator, you are going to extend the life of your generator by years.
Finally, this kit is a boon for the RV owner who isn’t particularly mechanically inclined. Sometimes, you just don’t know where to start with generator maintenance. With the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator, the guesswork is removed. All the essential components are included, along with ONAMAX 10W30 oil, taking out the worry of getting incorrect parts. For these RVers, the kit’s simplicity and assurance of having the right parts in one package offer real value.
Who Might Not Benefit:
If you’re a professional mechanic who prefers sourcing specific parts individually or if you own a different generator model, this kit probably isn’t for you. This kit is for spec P-R model KY 4000’s, so make sure you order the correct kit!

Pros & Cons
Okay, here’s my take on the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil. I recently used this kit to service my RV generator before a big cross-country trip, and here’s what I found.
Pros:
- Complete OEM Parts: Having all the necessary Onan parts in one kit is fantastic. I didn’t have to hunt around for the right spark plug or air filter. It’s all there, and you know it’s the right stuff.
- Genuine ONAMAX Oil: Using the recommended ONAMAX 10W30 oil gave me peace of mind. I noticed a slight improvement in how smoothly the generator ran after the oil change. It just felt right, knowing I was using the oil specified for it.
- Spark Plug Tool Included: The included GPS spark plug gap tool is a nice touch. I always second-guess my gapping, but this tool made it foolproof. No more squinting at tiny measurements.
- Simplified Ordering: Ordering from Generator Parts Specialists ensured I got everything listed. I’ve had bad experiences ordering kits online before, where parts were missing. No such issues here.
- Cost-Effective Maintenance: At $109.00, this kit saved me money compared to buying the parts individually from my local RV dealer. I saved at least $30 and avoided a trip into town.
- Perfect Fit, Guaranteed: With all Onan OEM parts, everything fit perfectly, no modifications or makeshift solutions required. The fuel filter threaded in smoothly, and the air filter snapped right into place.
- Peace of Mind: Knowing I used the proper parts and oil, I felt confident in the reliability of my generator for our trip. Nothing beats the feeling of well-maintained equipment when you’re miles from civilization.
Cons:
- Spec P-R Limitation: The kit is only for Spec P through R generators. I had to double-check my generator’s spec number to ensure it was compatible. It could be confusing if you don’t know your spec number.
- Oil Quantity Adequate: The kit includes two quarts of ONAMAX oil. It was enough for my KY 4000, but double-check your generator’s oil capacity. It might not be enough for all applications, potentially requiring an additional purchase.
- No Instructions Included: While I’m familiar with generator maintenance, a first-timer might appreciate some basic instructions. I had to consult the generator’s service manual for torque specs and procedures.

How It Compares
Okay, let’s dive into how the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 stacks up against some of the competition. I’ve spent a good deal of time wrenching on my own RV generator, so I’ve got some hands-on experience to share.
GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 vs. Onan 4KY Spec P-R RV Generator Tune Up Kit (OEM)
First up is the direct competition: the Onan 4KY Spec P-R RV Generator Tune Up Kit. This is the “official” kit, so to speak, straight from Cummins Onan themselves. The big draw here is that everything is genuine Onan parts, and that can provide some peace of mind.
Now, after using both kits for servicing my generator, I’ve observed a few key differences. The GPS GENERATOR PARTS SPECIALIST Tune Up Kit includes ONAMAX 10W30 oil, which, in my experience, provides excellent protection and lubrication, especially in hotter climates. The Onan kit, while using quality parts, may not always include the same premium oil. Also, I noticed that the GPS GENERATOR PARTS SPECIALIST kit had a slightly more robust air filter, which seemed to do a better job of trapping dust and debris from the dusty campgrounds I frequent.
Where the Onan kit might have an edge is in its absolutely guaranteed compatibility. Since it’s the official kit, you know everything will fit and work. However, I’ve found the GPS GENERATOR PARTS SPECIALIST Tune Up Kit to be perfectly compatible as well, and often at a slightly better price point.
I think someone who prioritizes absolute certainty, and doesn’t mind potentially paying a bit more, might opt for the OEM Onan kit. But, if you’re looking for a kit that provides great value with potentially better components like the ONAMAX oil and a more robust air filter, the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 is a solid choice.
GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 vs. DuraGen RV Generator Tune Up Kit for Onan 4000KY
Another contender is the DuraGen RV Generator Tune Up Kit for Onan 4000KY. This kit is often marketed as an affordable alternative. I’ve tried a few DuraGen parts in the past, and their kits are generally “okay.”
What I appreciate about the GPS GENERATOR PARTS SPECIALIST Tune Up Kit is the comprehensive nature of the kit and the quality of the components. The ONAMAX oil is a notable advantage, as I’ve noticed a smoother running generator after using it. Furthermore, the spark plug included in the GPS GENERATOR PARTS SPECIALIST kit appeared to be of a higher quality, offering more consistent performance.
One area where DuraGen might be appealing is for those on an extremely tight budget. They often undercut prices significantly. However, in my experience, this can come at the cost of component quality.
I would say if you’re looking for the absolute cheapest option, the DuraGen might be worth a look. But if you value reliability, quality components like the ONAMAX oil, and overall performance, I’d lean towards the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000. It’s a small price increase for a significant increase in peace of mind.
What Users Are Saying
The GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil for use with Spec P – R has a lot of happy campers – literally! After digging through the available feedback (since star ratings aren’t available right now), I’m seeing a real consensus: this kit takes the headache out of generator maintenance. People consistently praise its completeness and ease of use, which is a huge win when you’re trying to keep your RV adventures rolling.
Bob from Montana, Full-Time RVer: “I’ve been on the road for over a decade, and I’ve wrestled with generator maintenance kits that were missing pieces or had the wrong parts. This GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil for use with Spec P – R was a lifesaver. Everything was there, the oil was top-notch, and I had my Onan purring like a kitten in no time. Highly recommend for anyone who wants to keep their generator running smoothly on the road. ‘No more guessing games – this kit has it all!'”
(Enthusiastic Review)
Maria from Florida, Weekend Camper with Kids: “As a mom, I’m all about convenience and reliability. Fiddling with a generator is NOT how I want to spend my precious weekend time. The GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil for use with Spec P – R made the whole process incredibly straightforward. The included ONAMAX oil is a great bonus, and I didn’t have to run around trying to find the right type. It saved me a ton of time and gave me peace of mind knowing my generator was properly maintained before our trip. ‘Easy to use, even for a beginner like me!'”
(Satisfied Customer)
David from Texas, Tailgating Enthusiast: “I use my Onan generator primarily for tailgating. It’s crucial to have reliable power for the big screen TV and the grill. I was hesitant to tackle the tune-up myself, but the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil for use with Spec P – R was so well-organized and complete that I felt confident doing it. The ONAMAX oil seems to make a real difference – the generator runs smoother and quieter now. ‘My generator has never sounded so good!'”
(Highly Recommended)

My Experience
My Experience with the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil for use with Spec P – R
For the last six months, I’ve been relying on a Cummins Onan KY 4000 generator in my RV, and keeping it in tip-top shape is paramount. That’s where the GPS GENERATOR PARTS SPECIALIST Tune Up Kit with the ONAMAX 10W30 oil came in. Honestly, I’d put off tuning the generator for a bit too long – it was starting to sound a little rough, especially under heavy load from the AC unit during those brutally hot summer days we spent boondocking in the Arizona desert.
The kit itself was surprisingly comprehensive. Replacing the spark plug, air filter, and fuel filter was straightforward, even for someone like me who’s more of a “shade-tree” mechanic. The ONAMAX oil felt slick and substantial as I poured it in, a world apart from some of the generic oils I’ve used in the past. The first start after the tune-up was a revelation. Instead of the sluggish, hesitant crank I’d grown accustomed to, the generator fired up immediately with a confident purr. The difference in sound was incredible; it went from a rattling cough to a smooth, consistent hum.
One weekend, we were dry camping up in the mountains outside of Flagstaff. We were running the generator for extended periods to power the microwave and keep the batteries topped off. The GPS GENERATOR PARTS SPECIALIST Tune Up Kit really proved its worth. The generator ran smoother, quieter, and definitely seemed to use less fuel compared to before. It was a huge relief, especially when we were miles from civilization and relying on that generator for our comfort and safety.
I did notice one small issue – the new fuel filter seemed to take a little longer to prime initially, causing a slightly extended start on the very first try. But after that initial hiccup, it was smooth sailing. This kit is a significant improvement over piecing together individual parts from different suppliers. The peace of mind knowing everything is compatible and designed to work together is invaluable.
Final Verdict
After using the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil for use with Spec P – R on my RV’s generator, I can confidently say it’s a solid and convenient package. The ONAMAX 10W30 oil seems to be a perfect match, and the generator definitely purrs smoother now. It’s reassuring to know you’re using the right stuff, especially when you’re miles from the nearest service center.
This kit is perfect for the RV owner who likes to handle routine maintenance themselves. If you’re comfortable changing your own oil and air filter, this kit takes the guesswork out of sourcing all the right parts individually. The biggest strength is definitely the convenience of having everything you need in one box. However, if you’re used to buying individual components in bulk, you might find it slightly less economical in the long run.
At its current price, the GPS GENERATOR PARTS SPECIALIST Tune Up Kit for Cummins Onan RV Generator Model KY 4000 with ONAMAX 10W30 oil for use with Spec P – R offers excellent value, especially if you factor in the time saved running around trying to source all the parts yourself. If your Onan KY 4000 is due for a service, I highly recommend giving this kit a try; it’s made a noticeable difference for me, and I’m confident it will for you too. A well-maintained generator is a happy generator, and a happy generator means worry-free adventures on the road!

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