I have a 1999, 8-cylinder Dodge Ram 4-wheel-drive crew-cab truck that has served me well towing my 1-ton pontoon boat. What would you recommend to replace it that might get a little better gas mileage and still provide a comfortable ride for four people? I tow only every other year or so — 800 miles round trip. Thanks!

I’d recommend that you replace it with a Toyota Avalon Hybrid, supplemented by a U-Haul rent-a-pickup once every other year.

A lot of our customers make the mistake of buying a car for something they do very infrequently. You know, they get an SUV that’s capable of seating eight people for the one trip per year they take to Grandma’s with Cousin Itt. And here you are, driving around every day, getting 13 mpg as penance for a chore you have to do only every two years.

An alternative is to get a comfortable family car that you can enjoy 103 out of 104 weeks every two years, and then just rent a pickup (or, even better, borrow one) for your biannual week at the lake.

I mention the Avalon Hybrid because I drove it recently and was impressed by its roominess and ride, and the nearly 40 mpg it got, city and highway. But you can get any car you like.

And then, when you want to haul the boat, you rent a pickup truck and put the towing wear and tear on that. It’s not cheap to rent a pickup; you might spend $500-$1,000 for the week. But do the math:

If you drive 20,000 miles a year and you’re getting 13 mpg, over two years you’ll spend $9,228 on fuel (assuming gas stays at $3 a gallon, which it probably won’t). If you drive that same 20,000 miles a year over two years in a car that gets 40 mpg, your fuel cost will be only $3,000.

So, even counting the pickup truck rental, you’d still come out ahead by $5,000 every two years! And you won’t have to pass over nearly as many parking spaces that you don’t fit in.

There are other options, too. If you really do need a pickup truck, or just want one, for whatever reason, I like the RAM 1500 with the V-6 diesel engine. That gets a combined 22 mpg, with an impressive 27 mpg on the highway, and it handles well, for a humongous beast.

Or you could check out the new aluminum-bodied 2015 Ford F-150, which I haven’t driven yet. But reportedly it will get similar mileage.

Or, keep your old truck around just for that one vacation week if you really want to.

But if it were me, I’d get a car, and live it up. Let us know what you decide.

We have two cars that are each driven about 4,000 miles a year. Since it will take 10 years or so to put 40,000 miles on the tires, should I consider replacing them after a certain number of years, instead of miles? If so, how many years do you recommend for replacement?

Well, the American tire industry recommends that tires be replaced every six years, even if the tread is not worn down. Of course, the American Couch Association also recommends that you replace your sofa cushions every three months due to flatulence. And I think both of those industries probably are erring on the side of caution. And increased sales.

Tires do dry out and degrade over time, due to exposure to sun and ozone in the air. I’m sure you’ve seen old tires that are covered in small cracks on the sidewalls. Those should be replaced.

They also can degrade in and around the tread, where most people don’t look. So that needs to be checked, too.

So my advice would be, starting at year six, have a mechanic you trust (and not necessarily a tire salesman) take a good look at your tires. You need a knowledgeable, non-interested party to do a visual inspection and tell you whether the tires are still good.

If your cars sit outside all the time and you live in a hot-weather climate, and you bought cheap tires to begin with, you may need tires after six years. If they’re garaged, or they’re particularly good tires, you could get seven, eight or even more years out of them while still driving safely.

And you want to factor in your driving habits, too. If 95 percent of your driving is from your house in a golf community to the clubhouse for lunch and back, the risk of catastrophic failure is low, because heat from high-speed driving is what tends to make tires fail suddenly.

Whereas, if you do a lot of highway driving, you’ll want to err on the side of caution and make sure your tires are not near the end of their lives.

By the way, if you’re not sure how old your tires are, you can check the sidewall. You’ll find a number there that says something like “2214.” That means your tires were manufactured during the 22nd week of 2014.

And if they’re not 6 years old yet, at least you’ll know when to throw them their next birthday party.

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