Across
1. Helical fastener formations
5. With 13-Across, Michelin or Goodyear products
8. Palindromic disc-brake item
9. Pre-owned vehicle (4,3)
10. Oil-cartel acronym
11. Cold-start engine speed (4,4)
13. See 5-Across clue
14. Circular-rubber sealing devices (1,5)
17. Auto assembly-plant need (3,5)
19. Dipstick marking
22. Stopwatch-monitored Indy interval (3,4)
23. Electric or air-powered noise makers
24. Body configuration, e.g. coupe or hardtop
25. Big-rig attachment
Down
1. Engine-power booster, briefly
2. Recycled tire
3. Suspension component, a.k.a. wishbone (1,3)
4. Slipping fan-belt sound
5. High-pitched stereo speakers
6. Drove at Indy
7. Internet car shoppers, informally
12. Tomorrow’s Technician, for example
13. Carmakers’ defect-driven programs
15. Shifter selection
16. Urban thoroughfare
18. Discharge a car loan
20. Alignment-machine beam, perhaps
21. US drag-racing body, briefly (1,1,1,1)