[Xphyle]

Hey everyone. As many people here are going to buying these brand spanking new Jeep Cherokees, I was wondering if anyone has any concrete data on how to properly break in a new Cherokee engine? Do you drive it hard, pedal to the floor? Gently? City stop and go? Highway? What's the best way to do it?

Thanks!

 

[Hudsonhawk]

The Users Guide that you can download from jeep.com has the break-in procedure on page 27. Towing requires additional break-in time and procedures.

 

[Xphyle]

The Users Guide that you can download from jeep.com has the break-in procedure on page 27. Towing requires additional break-in time and procedures.

Cheers. Here's the info in case someone else is curious:

ENGINE BREAK-IN RECOMMENDATIONS
• A long break-in period is not required for the engine and drivetrain (transmission and axle) in your vehicle.
• Drive moderately during the first 300 miles (500 km). After the initial 60 miles (100 km), speeds up to 50 or 55 mph (80 or 90 km/h) are desirable. • While cruising, brief full-throttle acceleration within the limits of local traffic laws contributes to a good break-in. Wide-open throttle acceleration in low gear can be detrimental and should be avoided.
• The engine oil installed in the engine at the factory is a high-quality energy conserving type lubricant. Oil changes should be consistent with anticipated climate conditions under which vehicle operations will occur. For the recom- mended viscosity and quality grades, refer to “Maintaining Your Vehicle”.
NOTE: A new engine may consume some oil during its first few thousand miles (kilometers) of operation. This should be considered a normal part of the break-in and not interpreted as an indication to an engine problem or malfunction.

 

[Hudsonhawk]

This is from the Owner's Manual specifically about trailer Towing:

• Do not tow a trailer at all during the first 500 miles
(805 km) the new vehicle is driven. The engine, axle
or other parts could be damaged.

• Then, during the first 500 miles (805 km) that a
trailer is towed, do not drive over 50 mph (80 km/h)
and do not make starts at full throttle. This helps
the engine and other parts of the vehicle wear in at
the heavier loads.

 

[develmann]

I typically like to change the oil at 300-500 miles in case there is any metal still in the system. It might be overkill, but that's what I usually do.

 

[Xphyle]

I noticed that the owners manual states 87/89 Octane gas for the Pentastar V6. Does that mean you can use either one?

 

[develmann]

I noticed that the owners manual states 87/89 Octane gas for the Pentastar V6. Does that mean you can use either one?

I think that's the listing with most modern cars now. I doubt it would make much of a difference. I hear some people say they get better mileage with 89 octane, but I have never seen much difference. Octane is really all about compression. Since these cars are not (yet) turbocharged or Direct injected I wouldn't worry about 89 octane.

 

[brianch]

everyone has their own method. if you dont know what to do. follow the users manual.

 

[checkers]

get on it and get on it good. Engines need to be stressed for them to realize peak performance, starting with the break in period. You need to get the Cherokees components ready for the stress levels you intend to lay on it. You cant do that by babying it.

My favourite analogy is that you dont train for a 20K marathon by walking 5K every night.

Oh and heres a great site explaining the virtues of hoonage during the break in period http://www.mototuneusa.com/break_in_secrets.htm

 

[Hudsonhawk]

That is great for engines but that is not the only thing you are breaking in. You are also breaking in the gears in the transmission and the axles. If ths is not done correctly the heat generated by heavy loads can literaly melt the gears.

I have seen the results in my buddies off-road shop. Someone will come in and get new gears then go out and drive 70 MPH for hours on the highway. The worst set I have seen were worn down to a knife edge in a matter of a week or so. The owner brought it back in complaining of severe driveline lash.

You have to give the gears a chance to heat up and cool down to harden them correctly for long life.

 

[Erie-Eyes]

Cheers. Here's the info in case someone else is curious:

ENGINE BREAK-IN RECOMMENDATIONS
• A long break-in period is not required for the engine and drivetrain (transmission and axle) in your vehicle.
• Drive moderately during the first 300 miles (500 km). After the initial 60 miles (100 km), speeds up to 50 or 55 mph (80 or 90 km/h) are desirable. • While cruising, brief full-throttle acceleration within the limits of local traffic laws contributes to a good break-in. Wide-open throttle acceleration in low gear can be detrimental and should be avoided.
• The engine oil installed in the engine at the factory is a high-quality energy conserving type lubricant. Oil changes should be consistent with anticipated climate conditions under which vehicle operations will occur. For the recom- mended viscosity and quality grades, refer to “Maintaining Your Vehicle”.
NOTE: A new engine may consume some oil during its first few thousand miles (kilometers) of operation. This should be considered a normal part of the break-in and not interpreted as an indication to an engine problem or malfunction.

The above instructions are similar to the break-in instructions on all my previous new vehicles. i have always followed these instructions to the letter, and have never to date had engine or transmission problems, and I have been buying new vehicles since 1966.

 

[Peter]

Well as soon as our arrives it will be from the dealer show room straight to the nearest national forest for a nice long drive to see what she can do.

Drive it like you would your normal car/truck/Jeep but just don't baby the thing....

 

[thewifes'wheeler]

Engine builder here... the drive it like you stole it method does not work for break in. the piston rings need to seat with the crass hatchings of the bore. excessive stress cause blow by with the tight tolerences and damages the rings.

 

[3737]

I was contemplating buying a Jeep and within days driving about 8.5 hours, mostly highway. It sounds like that's okay if I keep the first 60 mi local? And I would have plenty of opportunity for those brief full-throttle accelerations. Or is that much highway time right out of the gate pushing all those other parts too much? I could break up the long drive for an overnight if that's advisable. Or, :-( , wait to get a new car until after I finish this next long trip. Thoughts on this specific situation?

 

[bruceg]

I was contemplating buying a Jeep and within days driving about 8.5 hours, mostly highway. It sounds like that's okay if I keep the first 60 mi local? And I would have plenty of opportunity for those brief full-throttle accelerations. Or is that much highway time right out of the gate pushing all those other parts too much? I could break up the long drive for an overnight if that's advisable. Or, :-( , wait to get a new car until after I finish this next long trip. Thoughts on this specific situation?

The day I bought my Cherokee I drove it home 30 minutes @ 75mph... It's just fine. lol

 

[onefunkar]

one big break in problem is in the winter when they broom the cars and plow the lot these new cars can idle for half and hour at a time. so much for break in

 

[Jeepster1]

Engine builder here... the drive it like you stole it method does not work for break in. the piston rings need to seat with the crass hatchings of the bore. excessive stress cause blow by with the tight tolerences and damages the rings.

Very good point. Anyway what is couple hundred miles to prep your new Cherokee?
Most overlooked are the axles. Those gears if overheated before they "temper" will be toast. It takes heat up and cool down to accomplish this. Easy for the first 60 miles as the break in says.

 

[EkC]

Well as soon as our arrives it will be from the dealer show room straight to the nearest national forest for a nice long drive to see what she can do.

Drive it like you would your normal car/truck/Jeep but just don't baby the thing....

That will be easy for me since I live in a national forest !

 

[Afemoralez]

Future 2014 Trailhawk owner here.... Purchasing a new and first Jeep in the next two weeks. I am stationed in Italy. Buying the Jeep from a base 4 hours away. The Jeep has about 100 miles on it from test drives. Upon purchase I will need to try it home 4hrs, 250 miles. Any advice on how to make sure I get a good break it and don't cause any damage. The speed limit will be about 85 mph hours but I'm already planning on staying. At about 60 mph from what I have read in this thread. Thanks in advance!

 

[TedB]

:grin:I drove by the break-in instructions for the first 500-600 miles and then took off, heavily loaded (the car, not me) on a 2,300 mile round trip across two mountain ranges, on the 4 lanes, 2 lanes, back roads and off roads. When we got home, the T'Hawk was nicely broken in and has purred like a kitten ever since, or maybe more like a tiger!