# How many miles is a cold start equal too?

#### driven2services

I was just thinking...(I hate when I do that)...I know a cold start puts alot more wear on the engine than actually driving, but how much more? How many "warm miles" do you guys think a cold start would be equivalent to?

#### Quattro Pete

I've seen a figure of about 400 "warm" highway miles before. Not sure what the basis for this was though.

#### Jay

Robert Sikorsky, who has written several books on automobile longevity, said that the wear penalty for a cold start is equivalent to about 500 highway miles. This was 30 years ago, though.

#### Jelly

Maybe I'm missing something here, but... 365 days in a year. Say you go to work 225 days/yr. At minimum, start car once in morning cold and once in afternoon cold. 225 days x 2 cold starts a day = 450 cold start per yr. 450 cold starts x 400 miles = 180,000 miles 450 cold starts x 500 miles = 225,000 miles So following these guesses, at least according to Sikorsky, your putting 225,000 miles of wear on your engine a year just by cold starts? This can't be right...

#### driven2services

quote:
Originally posted by Jelly: Maybe I'm missing something here, but... 365 days in a year. Say you go to work 225 days/yr. At minimum, start car once in morning cold and once in afternoon cold. 225 days x 2 cold starts a day = 450 cold start per yr. 450 cold starts x 400 miles = 180,000 miles 450 cold starts x 500 miles = 225,000 miles So following these guesses, at least according to Sikorsky, your putting 225,000 miles of wear on your engine a year just by cold starts? This can't be right...
It could be, because all cars have alot of cold starts. Just think if you started your car once, found a way to change the oil while it's running, and drove on a track until it died. You'd probably get 4-500,000 miles out of it...

#### Chris B.

Wow! 500 miles! That is hard to believe!

#### driven2services

quote:
Originally posted by Chris B.: Wow! 500 miles! That is hard to believe!
Yeah, I'll think twice next time about starting up just to move my truck and make more room in the garage...

#### Blue636

500 miles of wear has got to be the most stupid thing I've ever heard in my life.

#### TallPaul

quote:
Originally posted by ZmOz: Yeah, I'll think twice next time about starting up just to move my truck and make more room in the garage...
This is also hard on the engine because of the cold shutdown, leaving all the combustion blowby to settle into the oil instead of most of it burning off as it would in an engine brought up to full operating temperature. That is why short trips (say under 10 or so miles) are so hard on engines and oil. This is probably worse than the cold start, at least in summer.

#### XS650

quote:
Originally posted by Blue636: 500 miles of wear has got to be the most stupid thing I've ever heard in my life.
When in doubt, follow the money. It must have come from someone selling a magic elixor or gadget to mitigate the effects of cold starts. Most cars get used 6 or 7 days a year with 2 cold starts a day, so figure 13 cold starts a week for 52 weeks a year. 13 x 52 x 500 = 338,000 equivilant miles per year from cold starts. A modern car with reasonable care lasts 10 years and 150,000 miles before needing internal engine work. 338,000 x 10 + 150,000 miles = 3,530,000 equivilant miles on an engine before needing internal work. Buuuul, pucky

#### Blue636

I guess it could very well be a money scheme. Whatever happened to that DuraLube stuff? I remember all those infommercials on TV about how incredible and amazing it was. I still see it on the shelves, but who ever really used that stuff?

#### driven2services

But think about it this way...they only last 150,000 miles BECAUSE of all the cold starts. Without them it would last MUCH MUCH longer. 500 might be a little much...but it's got to be over 100...

#### Grossomotto

All my driving is short trips. Sometimes 50 cold starts a day. That's why I've switched to Delvac 1 5W40. By these numbers, I put 25,000 miles a day on my truck? That's over 9 Million Miles a year. I plan on keeping this truck for at least 20. So, I figure over 180,000,000 miles the truck will be equal to!

#### Grossomotto

Also, what about extended drain? Can I go the entire day (25,000 miles) with the same oil? Or should I shorten the OCI to 3-4 hour intervals? This is gonna get expensive.

#### olddognewtrks

Let's take a different tack here...If someone would produce a REASONABLY priced pre-luber (say \$100 US ready to install), a lot of us would get one, and our start-up wear would be reduced by (wild guess) 50-90%. Of course, most citizens aren't oil nutzo's like us , and wouldn't/couldn't care less, and so my dream of cheap pre-lubing dies yet again. I have checked out piecing a pump together from assorted sources,(agricultural, boating) and it's still at least \$150-200 after I design the system myself. If anyone has any hints/leads/etc for a cheap pump (say \$75), holler. I'd like to check into designing and marketing systems myself, but I don't have the facilities, money, or resources. Darn, now I won't get rich either!

#### DavoNF

Yes, a pre-oiler would save a lot of start-up wear. I've got a better idea. We need a little electronic gizmo that would prevent the car from starting on the first key-turn. So you you crank it up, get the oil pressure up, release the key to start on the next turn. Any venture capitalists out there? Dave

I was once a member of the purchasing standards committee as an employee of my city. In one of our meetings we were informed by people supposedly in the 'know' that a cold start just to move a vehicle a few feet in the driveway is equal to 500 miles of operating temperature driving in wear. This is not my claim. I just listened with keen interest. We did set standards on items to be purchased by the city and automobiles and services was sizeable part of the budget.

#### moribundman

The figure I've heard was 200-400 km, but that was regarding a cold start at freezing temperatures.

#### Francis

I read once in an Oil report, that it was proven that if you just let your car idle for no less than 20 Seconds before Revving or Driving that this increased you chances of long engine levity by over 50%.

#### therion

quote:
Originally posted by Francis: I read once in an Oil report, that it was proven that if you just let your car idle for no less than 20 Seconds before Revving or Driving that this increased you chances of long engine levity by over 50%.
That is true, you MUST let the oil reach all the vital areas of the engine & warm up just a alittle bit BEFORE putting strain on the engine. Also, you shouldn't idle it too long (i.e. like 10 minutes) that is bad for the engine as well and will take forever to warm up. The best way to warm up a vehicle is to idle it for a min or so then drive really slow until the coolant guage goes to normal operating temp. Thats what i think any thoughts??