Symptoms
On sunroof-equipped trucks: wet headliner or carpets, rust bubbling at the base of the A-pillars, a musty cab.
The fix, step by step
- Owners report blocked sunroof drains rusting out A-pillars on trucks fitted with a sunroof.
- Clear the drain tubes with trimmer line or low-pressure air, check the outlets aren't crushed, and replace hardened top and window seals.
- Treat any surface rust in the pillars before it goes through.
Tools & part numbers
- Trimmer line
- low-pressure air
- rust converter
- new seals
Where to buy the parts
Body seals, weatherstrip & trim — 1987 4Runner catalogRockAuto ↗
Hunting a used or discontinued part? Search eBay Motors for Toyota 4Runner 1st Gen parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.