Across
1. Underbody components, collectively
5. ’60s gas slogan, "Put a ____ in your tank"
8. Gear or compression trailer
9. Dashboard channel (3,4)
10. Toddler’s Tonka-truck terrain
11. Under-dash area
13. Clutch components
14. Major engine castings
17. Big-rig wheel count, often
19. Gear teeth
22. RWD car’s differential, slangily (4,3)
23. Budget and Hertz rival
24. OBD scan-tool data
25. Alignment-rack measurement, maybe (4,3)
Down
1. Components returned for rebuilding
2. Radio adjunct in auto glass, often
3. Brake-system footwear
4. Auto-tool brand since 1920 (4,2)
5. Accelerator
6. Dash dial
7. Old-car noises, often
12. Motorcyclists’ attire, often
13. Post-1977 tire-sizing system (1,6)
15. Antifreeze and water mixture
16. Power-boosting exhaust manifold
18. Brinks-truck occupant
20. Oil-burner’s output
21. Aftermarket auto-parts retailer