Frequently Asked Questions About Mack CH/CHN/CHU Truck Steering Parts & Acc.

Will these steering parts fit my specific Mack CH model year?

Most steering components for Mack CH, CHN, and CHU models are compatible across years 1988-2007, but there are important exceptions. Power steering pumps and gear boxes can vary between early models (1988-1999) and later models (2000-2007). Always check the product description for specific year ranges, or contact our support team with your VIN number to ensure proper fitment. Pay special attention if you have a CHU model, as some steering linkage components may differ from standard CH models.

What are the signs I need to replace my steering gear box or power steering pump?

Common indicators include excessive play in the steering wheel (more than 2 inches), steering wheel vibration at highway speeds, difficulty turning, whining noises from the pump, or visible fluid leaks around the gear box seals. For Mack CH trucks, steering issues often start gradually - if you notice increased effort required to turn or a wandering sensation while driving straight, have your steering components inspected immediately. These trucks are known for developing wear in the sector shaft and input shaft areas after 300,000-400,000 miles.

Can I install these steering parts myself, or do I need special tools?

While experienced mechanics can install most steering components, certain parts require specific tools and procedures. Tie rod ends and drag links can typically be replaced with standard hand tools and a pickle fork. However, steering gear boxes require proper alignment and adjustment of sector shaft end play and worm bearing preload - incorrect installation can cause premature failure or unsafe handling. Power steering pumps need proper belt tension and bleeding procedures. We recommend professional installation for gear boxes and pumps, while tie rods and stabilizers can be DIY projects with proper safety precautions.

What's the difference between OEM and aftermarket steering parts for my Mack?

OEM parts are manufactured to Mack's original specifications and typically carry longer warranties but at premium prices. Quality aftermarket options from brands like TRW, Saginaw, and Sheppard often match OEM performance at 30-50% less cost. The main differences are in warranty coverage (usually 1 year vs. 2 years) and minor variations in casting designs. For high-mileage trucks or fleet applications, many operators choose aftermarket without sacrificing reliability. Avoid ultra-budget options that use inferior seals or bearings - these often fail within months.

How often should I service my power steering system to prevent major repairs?

Mack recommends checking power steering fluid levels weekly and changing the fluid every 100,000 miles or 2 years. However, severe-duty applications should service more frequently - every 50,000 miles. Use only approved power steering fluid (Mack EO-M or equivalent ATF+4). Regular maintenance prevents contamination that causes pump wear and gear box seal failure. Also inspect steering shaft u-joints every oil change, check for loose components, and ensure proper tire pressure to reduce strain on steering components. Preventive maintenance typically extends component life by 40-60%.