Getting the lead out
Q
: Thought I’d comment on the item where you responded to a question about motor oil specs for an old vehicle, and using modern oils in older vehicles. Your answer was absolutely correct. But it is possible that the letter writer (or his/her sources) confused oil additives with the phasing out of lead in gasoline, and the resulting concern about wear/ deposits on the valve seats? Modern materials and gas additives solved this issue, and it should be a non-issue for a vehicle driven as infrequently as the writer’s but some still see it as a concern.
A.S., Littleton, Massachusetts
A
: Good point. Leaded gasoline (containing tetraethyl lead) created a buildup on the valve seats, which cushioned the valves when they closed preventing valve recession. There was wailing and gnashing of teeth from collectible car owners when lead was initially phased out to prevent catalytic converter damage. Another compound, ZDDP, which helped reduce friction with motor oil, was also removed resulting in damage to collector car engines with flat-tappet camshafts and lifters. Things have quieted down, probably because, as you noted, those vintage cars are usually neither driven hard nor for great distances. Many are trailer queens.
Q
: I own a 2002 Dodge Grand Caravan. It runs great but I have a problem with the seat belt. I cannot adjust it so it is comfortable. It rubs under my chin and can’t be lowered anymore. I’ve tried every setting, all the way up and down. I wear it all the time, no matter how uncomfortable it is. Any suggestions for making it comfortable?
A
C.P., Inverness, Illinois
: I have the same problem in the summer when wearing a T-shirt. I have tried a clip that connects the shoulder belt to the seat belt, thus moving the shoulder belt to the left a little. Not so great and comes apart too often. I tried a fuzzy tube-shaped item that was acceptable but bulky. My latest is a satin-like padded square that wraps around the shoulder belt and then closes with Velcro. So far, the winner.