Manual Transmission Shift Patterns Explained

Every Eaton Fuller manual uses the same basic H-pattern, but the range switch and splitter change how many gears you actually access. Here's how each one lays out.

The Shared H-Pattern

All Eaton Fuller manuals share a 4-position H-pattern: Low / 1 / 2 / 3 / 4. The difference is what the range switch (on the front of the knob) and the splitter button (on the side) do.

9-Speed and 10-Speed

• Low is the starting position (often used only for backing or heavy loads).
• Shift 1 → 2 → 3 → 4 in low range.
• Flip the range switch up to enter high range.
• Shift back to the 1 position — now it's 5 — and continue 5 → 6 → 7 → 8.
• A 10-speed adds a splitter that splits the top gears into high/low.

13-Speed

• Same base as the 9-speed: Low, 1–4 low range, flip, 5–8 high range.
• The splitter lets you split the top four gears (5–8) into low and high — so 5L, 5H, 6L, 6H, 7L, 7H, 8L, 8H.
• That gives you 13 forward positions.

18-Speed

• Same base H-pattern as the 9-speed.
• But the splitter works on every gear, low and high range.
• So every position has a low and high split: 1L/1H, 2L/2H, 3L/3H, 4L/4H, then flip the range and repeat 5L/5H through 8L/8H.
• That's 16 split gears plus Low (direct and low-low), totaling 18.

Reading the Knob

• Range switch (front, thumb): switches between low and high range.
• Splitter button (side, index finger): splits the current gear into low/high.
• You only move the stick through 4 physical positions per range — the switches do the rest.

Pro Tip

Most experienced drivers start in Low, then go straight to 2H or 3H depending on the load, skipping gears to save fuel. The 18-speed's flexibility is exactly why heavy-haul operators love it — you can always find the perfect RPM for the grade and the load.

Want to practice before you buy? Find a manual truck on 3PedalSemi and ask the seller about a pre-purchase inspection.