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Short trips worse on big engine or small engine?

My wife drives a V-10 Ford Excursion. She drives tons of short trips (5 - 10min)approx 600 to 700 miles per month. Is this type of driving worse for a large engine and more tolerated by a smaller V-8 or V-6? Her rig has 100,000mi. I use Mobil 1 and use a 7500 OCI.

I don’t think the size of engine matters, these short trips are rough on any engine. Are there any trips each week that get the engine fully warmed up? If not, there should be. Something like a 30 minute drive on the freeway would let the oil heat up fully to get rid of water and any condensed fuel.

Short trips are hard on any engine, regardless of size.

I suggest you follow the “extreme service” schedule as far as oil change intervals go.

In theory a smaller engine might work harder, reach operating temp faster, etc. In real world no difference. This is “severe” service and your maintenance routine should use the severe service schedule.

Your current OCI is way too long if those 7500 miles are taking more than 4 months.

This is one topic where size doesnt matter…lol

Short trips, especially in cold weather, are hard on any engine, but a smaller engine works harder and warms up quicker.

I had first hand experiencxe of this in the Arctic; the local oil company I worked for specified all their passenger and light truck vehicles with the smallest engine and block heaters. The big V8s never warmerd up properly on short trips and had lots of sludging.

Agree that this vehicle should have oil and filter changes every 3500 miles or so, since the short trip operation is the worst possible duty, and synthetic oil does not change that fact one bit.

Unless your wife pulls a trailer or carries large loads, the best vehicle for her would be a compact hatchback with the smallest engine available.

The Mobil-1 is helping things, I would say, but with any engine, you really need to get it warmed up thoroughly once in a while to ‘burn off’ impurities in the oil and keep excessive carbon from building up. It may be just my opinion, but I think big engines that never get to stretch their ‘legs’ tend to suffer more. I would lower the OCI to 5,000 miles with this type of driving, especially in these winter months.

The long oil change interval is likely doing more harm to the engine than the short trips are.

Well there might be a reason to drive a monster like this on such short trips. I cannot think of one. It is not a work truck, right. How about a small sedan?. A small 4 cylinder will get warm a lot faster than this monster. This engine has issues at this oil change.

I agree that the size of the engine probably isn’t a factor, but I will buck the trend about how much damage is being done to the engine because of the short trips.

Yes, there is moisture building in the exhaust system because it might not be reaching full operating temp, but I don’t think your wife’s shirt trips are hurting the engine. With old fashioned carburetors, while the engine warms up, the mixture is rich, so a lot of gasoline is being dumped into the cylinders until the engine warms up. With electronic fuel injection, the warm-up fuel mixture is rich, but the computer does a better job of metering the air/fuel mixture. With old fashioned carburetors, they pretty much have two modes; warming up, and already warm. With EFI, the transition is smooth, and the air/fuel mixture is leaned out pretty well after just a few minutes.

I would probably shorten my OCI to 5,000 miles and not give it any more thought. It’s nothing I would worry about.

The size of the engine is irrelevant but the oil change interval is way too long. This may only be discovered when a problem surfaces and by then it will be too late, if not already.

At 23 miles per day, I think she’s driving long enough. The oil should be changed once every six months. 3,000 miles would come sooner and be better for that type of driving.