Update 5:21 p.m.:
Though most of the westbound SR 60 was reopened midafternoon Friday, the Grand Avenue entrance ramp to the freeway was shut and was to remain so at least until 8:30 p.m., the CHP reported.
A crash involving two big rigs on the westbound state Route 60 in Diamond Bar Friday caused a large oil spill and snarled traffic most of the day, the CHP reported.
The crash near Grand Avenue was reported at 10:14 a.m.; there was still one freeway lane shut at 3 p.m., according to the California Highway Patrol.
About 75 gallons of diesel fuel spilled from one of the rigs -- one rig was a gravel hauler, the CHP reported.
No injuries were reported.
The fuel did not go into the drains, just traveled less than a half-mile west of the crash, the CHP reported.
A SigAlert was issued for about 2.5 hours; a far right lane remained closed Friday afternoon, just as rush hour was due to begin.