2007 Sierra 2500 w/Duramax - New Engine Break In Required?

[TopNotch]

We have a 2007 GMC Sierra Classic 2500 pickup. The dealer is replacing the engine after a month of trying other options to fix it.

We were out of state when our truck broke down and we were towing a 26' travel trailer. GM is telling us that there is no break in required for the new engine and that we can tow our trailer home immediately when we go to pickup our trailer. Is this true... that replacing the engine in an existing vehicle with 90,000 miles on it that there is no break in required??? This doesn't sound right to us and we don't want to damage anything right off the bat since almost immediately our route will endure some climbs.

 

[happy 2011]

Read this http://www.mototuneusa.com/break_in_secrets.htm

This is what i belive in as well (30 year tech) and do it on all my motors bikes ,boats , cars and tks (have had about 15 new motors plus all i have rebuilt)

never had one go bad yet!

 

[GMC Customer Service]

We have a 2007 GMC Sierra Classic 2500 pickup. The dealer is replacing the engine after a month of trying other options to fix it.

We were out of state when our truck broke down and we were towing a 26' travel trailer. GM is telling us that there is no break in required for the new engine and that we can tow our trailer home immediately when we go to pickup our trailer. Is this true... that replacing the engine in an existing vehicle with 90,000 miles on it that there is no break in required??? This doesn't sound right to us and we don't want to damage anything right off the bat since almost immediately our route will endure some climbs.

Page 423 of your owner’s manual says that you should not tow a trailer during break-in and page 231 has more information on breaking in your vehicle:

Your vehicle does not need an elaborate break-in. But it will perform better in the long run if you follow these guidelines:
• Keep your speed at 55 mph (88 km/h) or less for the first 500 miles (805 km).
• Do not drive at any one constant speed, fast or slow, for the first 500 miles
(805 km). Do not make full-throttle starts. Avoid downshifting to brake, or slow, the vehicle.
• Avoid making hard stops for the first 200 miles (322 km) or so. During this time the new brake linings are not yet broken in. Hard stops with new linings can mean premature wear and earlier replacement. Follow this breaking-in
guideline every time you get new brake linings.
• Do not tow a trailer during break-in. See Towing a Trailer on page 423 for the trailer towing capabilities of your vehicle and more information. Following break-in, engine speed and load can be gradually increased.

Thanks,
Laura
GMC Customer Service

 

[miserman]

The manual does state not to tow while breaking in ,but what type of damage would result is this was done ?

 

[Z15]

The owners manual is for a new vehicle and its taking into consideration more than just the engine. Everything is new, brakes for instance are one factor that are greatly influenced by proper break-in, also the rear differential. If those two components get too hot that can relate to shorter life span.


So its not just about the engine with the owners manual. I would say, go ahead and tow.

 

[miserman]

Thanks, I purchased a 2006 Sierra 5.3 with only 5300 miles and later learned it was used only for towing a camper to Fla. twice each year. This concerns me about the breakin on this vehicle.

 

[Z15]

I would not worry about it. For all you know it was broken in just fine.

Keep in mind these are guidelines....

Your vehicle does not need an elaborate break-in. But it will perform better in the long run if you follow these guidelines:

 

[GMC Customer Service]

The manual does state not to tow while breaking in ,but what type of damage would result is this was done ?

Unfortunately we don’t have that information, we just know that it could affect how the vehicle runs in the long term.

Thanks,
Laura
GMC Customer Service