Clearance + restrictionCited official sources
I-5 Grapevine — Tejon Pass California
6% sustained. CHP brake checks. The Los Angeles approach.
I-5 between Los Angeles and Bakersfield crosses Tejon Pass (4,144 ft) via a section locally called 'the Grapevine.' The descent from Tejon Pass into the San Joaquin Valley is a 6% sustained grade for about 12 miles. The California Highway Patrol routinely operates brake-check stops at the top of the descent. Truck (and RV) brake fade is the recurring danger.
Frame: a highway in California — not this route.
- Tier
- Clearance + restriction
- State
- California
- Sources
- Cited official (.gov / .org)
Descent management
From Tejon Pass (4,144 ft) the descent into the San Joaquin Valley is 6% sustained for 12 miles. In a Class A motorhome at 25,000 lbs gross weight, sustained service braking will overheat rotors within 5-7 miles. Engine braking is required.
For gas engines, downshift to 2nd or 3rd gear before the descent begins. For diesel engines, engage the exhaust brake. Maintain descent speed in the 50-55 mph range — don't try to do the speed limit on the brakes.
Pull off at the Lebec or Frazier Park exits if brakes feel hot or smell. Cool 20 minutes before continuing.
Real warnings
Brake fade is fatal
Vehicles have crashed because of overheated brakes on the Grapevine descent. Use engine braking.
Wind closes the Grapevine periodically
High wind closures, especially for high-profile vehicles. Check Caltrans before transit.
Ice in winter
Tejon Pass area gets snow + ice. Chains may be required.
What Caltrans + CHP doesn't tell you
Caltrans posts grade and weather information clearly. CHP brake-check program is genuinely useful — a free pre-descent safety check.
Many RV drivers underestimate the descent until they smell hot brakes. Don't be one.
Frequently asked questions
- Is the Grapevine open year-round?
- Mostly. Winter closures during storms. Caltrans posts.
- Should I drive at night?
- Avoid heavy summer traffic by driving early morning or late night, but watch for wildlife and visibility.
Authoritative sources
Verify current conditions with state DOT 511 systems before departure. RV restrictions may change. Weather may close roads.
Planning an RV trip along I-5 Grapevine?
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