A Guide to Transmission Filter Kits for the 2008-2019 International ProStar
Keep your ProStar's transmission protected and shifting correctly by choosing the right filter kit.
- You must identify your specific transmission (e.g., Eaton or Allison) to buy the correct filter kit.
- A clogged filter can cause shifting problems, but so can electrical issues; a filter change is a key maintenance step.
- Quality aftermarket brands like Wix and ATP are reliable, cost-effective alternatives to OEM filters.
- Change the filter every time you change the fluid, following the interval for your truck's specific use (line-haul vs. severe duty).
Is Your Transmission Filter Clogged?
A dirty or clogged transmission filter can't clean the fluid properly. This can lead to serious transmission problems. If you notice any of these signs with your ProStar, a failing filter could be the cause.
- Rough or Delayed Shifting: The truck may hesitate or jerk when shifting gears. This can be caused by contaminated fluid affecting the hydraulic pressure in the valve body.
- Unusual Noises: You might hear a whining or buzzing sound from the transmission. This can happen when the filter is clogged and restricts fluid flow to the transmission pump.
- "General Transmission Fault" Light: The dashboard may display a "Gen Trans Flt" warning. 🎬 Watch: Troubleshooting the Gen Trans Flt error and clutch actuator. While this can be caused by many issues, including electrical problems, it can also indicate a problem with fluid flow or pressure related to a clogged filter.
- Dark or Burnt-Smelling Fluid: Healthy transmission fluid is typically bright red. If you check the fluid and it looks dark brown or smells burnt, it's a sign the fluid is old and the filter is likely overdue for a change.
Known Issues, Recalls, and Bulletins
Transmission Clutch Recall
Navistar issued a recall for 2018-2019 International ProStar models equipped with Eaton ECA automated manual transmissions (NHTSA Campaign Number: 18V826000). An internal component in the clutch could fail, potentially causing the truck to move unexpectedly. The solution was a recalibration of the Transmission Control Module (TCM) performed by dealers. While not a filter issue, it highlights the complexity of the ProStar's transmission system.
The ProStar has many Technical Service Bulletins (TSBs), but none point to a widespread defect with the transmission filters themselves. However, many shifting problems that seem like a bad filter can actually be caused by electrical issues, like poor voltage to the transmission's computer or bad wiring connections.
Choosing the Right Aftermarket Filter Kit
Before buying a kit, you must know which transmission is in your ProStar. The most common are automated manuals from Eaton Fuller or automatics from Allison. They use different filters.
- Eaton Transmissions often use a single, remote-mounted spin-on filter.
- Allison Transmissions typically use a kit with two filters: one inside the transmission pan and one external spin-on filter. 🎬 See this walkthrough for an Allison transmission fluid and filter service.
Pro Tip: Check your truck's service manual or look for identifying marks on the transmission case to confirm the model before ordering parts.
Aftermarket Brand Tiers
For a part like a filter, a quality aftermarket brand offers performance similar to OEM at a better price. Both Wix and ATP are common aftermarket choices for the ProStar.
- Tier 1 (High Quality): Wix
Wix is a well-respected brand in the heavy-duty truck industry, known for making high-quality, reliable filters. Their filters are built to meet or exceed OEM specifications, providing excellent filtration and durability. Many professional mechanics trust Wix for heavy-duty applications. - Tier 2 (Good Quality): ATP
ATP is a solid choice that often comes at a lower price. Their kits are known for including a unique "3rd Hand" pan gasket, which has special holes that grip the bolts to make installation easier. However, be sure to inspect the gasket upon arrival. There have been some reports of the composite gaskets being damaged from being folded in the box.
| Part Type | Estimated Cost |
|---|---|
| New OEM Kit | $80 - $250 |
| New Aftermarket Kit (ATP, Wix) | $12.56 - $132.96 |
| Shop Labor | $150 - $350 |
Frequently Asked Questions
How often should I change the transmission filter?
You should replace the transmission filter every time you change the transmission fluid. For Eaton transmissions using long-life synthetic fluid, this could be up to 500,000 miles for line-haul use. However, for severe service like construction or dusty environments, the interval should be much shorter, perhaps every 15,000 to 50,000 miles. Always follow the service interval recommended by the transmission manufacturer.
What is included in a transmission filter kit?
This depends on the transmission. A kit for an Eaton may just be a single spin-on filter. A kit for an Allison will typically include two filters (internal and external) and all the necessary O-rings and gaskets for a complete service. Some aftermarket kits, like those from ATP, also include a new transmission pan gasket.
Can I replace the filter myself?
Yes, if you have the right tools and experience. The job involves draining a large amount of fluid, safely working under a large truck, and correctly installing the new filter(s) and gasket. For spin-on filters, it's important to pre-fill the new filter with fluid before installing it. For pan-drop services, you must clean the pan and magnet thoroughly. If you are not comfortable with this, it's best to have a professional mechanic do the job.
🎬 Learn how to reset the transmission service light after your DIY job.Will a new filter fix my shifting problems?
It might. If the problems are caused by a clogged filter restricting fluid flow, a new filter and fresh fluid can make a big difference. However, shifting issues on a ProStar can also be caused by bad sensors, low voltage, or internal transmission wear. A filter change is a good first step in troubleshooting.
Helpful Videos
Technical Specifications
Kit contents vary by transmission type. Eaton kits are often a single spin-on filter. Allison kits typically include an internal filter, an external spin-on filter, and associated gaskets/seals.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- International ProStar: