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-   -   What is the breakin period prior to towing? (http://www.jeepgarage.org/f222/what-is-the-breakin-period-prior-to-towing-67734.html)

Mike V 11-09-2013 10:09 AM

What is the breakin period prior to towing?
 
Title says it all. I know todays engines are brokin at the factory so your just seating trans clutches and diff gears. What mileage do they recommend before you tow anything?

Thanks
Mike V

acilate 11-09-2013 11:55 AM

Re: What is the breakin period prior to towing?
 
I would advise reading the diesel supplement:

http://www.wk2jeeps.com/manuals/2014...diesel_2nd.pdf

There is no break in period. There are specific things they request you to do, though, such as varying the throttle while towing.

mtnmerlin 11-09-2013 01:56 PM

Re: What is the breakin period prior to towing?
 
Quote:

Originally Posted by Mike V (Post 927126)
Title says it all. I know todays engines are brokin at the factory so your just seating trans clutches and diff gears. What mileage do they recommend before you tow anything?

Thanks
Mike V

I thought I read 500 miles, but I cannot find where. The material below implies at 1000 miles. Certainly not in the first 100 miles.

More reading:

TheDieselStop.Com - www.thedieselstop.com

How to properly break in an engine with a focus on the VW TDI

Mike V 11-09-2013 04:00 PM

Re: What is the breakin period prior to towing?
 
Quote:

Originally Posted by acilate (Post 927184)
I would advise reading the diesel supplement:

http://www.wk2jeeps.com/manuals/2014...diesel_2nd.pdf

There is no break in period. There are specific things they request you to do, though, such as varying the throttle while towing.


If the factory wants you to drive a certain way... thats part of the breakin process. I forgot that diesel engines are not broke in at the factory due to the longer process.

Mike V

crabman 11-09-2013 04:30 PM

Re: What is the breakin period prior to towing?
 
No, even the big engines (Cat etc.) are normally run on a load cell when new, it isn't until their overhauled which often happens in place you have to worry about ring seal over much. You were correct that the primary concern is the diff and the trans, engine, brakes etc to a lesser extent.

If you talk to someone like Motive who actually makes them they will tell you to take it easy and alter speeds, preferably with heat cycling (stopping to allow a cool down) for the first miles. It's been a few years since I installed gears but I remember it being 50 to 75 miles more or less. Then just don't flog the bejesus out of it till 300 and you're done. Those instructions are for hardened gears that have been shot-peened and all that good stuff. Passenger cars typically come with softer gears that are more forgiving. The result of improper break in will be increased noise (gear whine) and weaker gears.

For me bottom line is going a few hundred miles isn't all that onerous, after that I'm not to awful worried about it.

acilate 11-09-2013 04:31 PM

Re: What is the breakin period prior to towing?
 
Quote:

Originally Posted by Mike V (Post 927277)
If the factory wants you to drive a certain way... thats part of the breakin process. I forgot that diesel engines are not broke in at the factory due to the longer process.

Mike V

I'm just quoting the instruction manual :)

"ENGINE BREAK-IN RECOMMENDATIONS
The diesel engine does not require a break-in period due
to its construction."

That is not to say there isn't a break in PROCESS. I find this explanation extremely lacking and would love to see more detail about this. I was just trying to provide you with the best available information.

Mike V 11-10-2013 08:34 AM

Re: What is the breakin period prior to towing?
 
Quote:

Originally Posted by acilate (Post 927296)
I'm just quoting the instruction manual :)

"ENGINE BREAK-IN RECOMMENDATIONS
The diesel engine does not require a break-in period due
to its construction."

That is not to say there isn't a break in PROCESS. I find this explanation extremely lacking and would love to see more detail about this. I was just trying to provide you with the best available information.

Thanks for clearing it up. I want to tow an empty 18 foot open trailer home from picking up the oil burner. I can easily drive it 300 miles before I tow the trailer. Some vehicles want at least 500 to a 1000.

Thanks, Mike

acilate 11-10-2013 02:10 PM

Re: What is the breakin period prior to towing?
 
I would imagine an empty trailer is nothing to worry about. This is no worse than putting a couple linemen in the back seat.

mtnmerlin 11-20-2013 10:38 PM

Re: What is the breakin period prior to towing?
 
I finally found this. From page 520 of the owners manual:

• 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.

LabRatICMP3 11-20-2013 11:20 PM

Re: What is the breakin period prior to towing?
 
Quote:

Originally Posted by mtnmerlin (Post 933417)
I finally found this. From page 520 of the owners manual:...

Maybe you should read page 7 & 8 from the Diesel Supplement. :D

The diesel engine does not require a break-in period due
to its construction. Normal operation is allowed, providing
the following recommendations are followed:
Warm up the engine before placing it under load.
Do not operate the engine at idle for prolonged periods.
Use the appropriate transmission gear to prevent
engine lugging.
Observe vehicle oil pressure and temperature indicators.
Check the coolant and oil levels frequently.
Vary throttle position at highway speeds when carrying
or towing significant weight.

NOTE: Light duty operation such as light trailer towing
or no load operation will extend the time before the
engine is at full efficiency. Reduced fuel economy and
power may be seen at this time.

mtnmerlin 11-20-2013 11:40 PM

Re: What is the breakin period prior to towing?
 
Quote:

Originally Posted by LabRatICMP3 (Post 933431)
Maybe you should read page 7 & 8 from the Diesel Supplement. :D

I have. The diesel supplement is not contradicting the OM. Reaching "full efficiency" is further along than the first 500 miles. Note that the diesel supplement is addressing the engine. The OM is addressing engine, axles, and other components (such as transmission and transfer case).

crabman 11-21-2013 08:16 AM

Re: What is the breakin period prior to towing?
 
Guys you can search break in on ring and pinion and other gear types, cut and paste follows...

In order to make them run cooler and quieter, new gears are lapped at the factory. However, they are not lapped under the same pressures that driving creates. The loads generated while driving force any microscopic high spots on the gear teeth back into the surface of the metal. This is called "work hardening". Work hardening is similar to forging in the way that it compresses the metal molecules into a very compact and hard formation. This can only be accomplished if the metal surfaces are lubricated and the gear temperature stays cool enough that the molecular structure does not change. If the temperature of the metal gets hot enough to change the molecular structure, it will soften the surface instead of hardening it. The greatest damage to a new gear set results from running for ten minutes or more during the first 500 miles when the oil is very hot. Any heavy use or overloading while the oil is extremely hot will cause it to break down and allow irreversible damage to the ring & pinion.

Recommended procedure for breaking in new gears: After driving the first 15 to 20 miles, stop and let the differential cool before proceeding. Keep the vehicle at speeds below 60 mph for the first 100 miles. I also recommend putting at least 500 miles on the new gear set before heavy use or towing. During the first 45 miles of towing, it helps to go about 15 miles at a time before stopping to let the differential cool for 15 minutes before continuing. This is necessary because not all of the gear tooth is making contact until it is heavily loaded. When towing, the teeth flex to contact completely, and cause the previously unloaded portion of the teeth to touch and work harden. It is very easy to damage the ring & pinion by overloading before the teeth are broken-in.

...End cut and paste. While this tidbit applies to ring and pinions specifically much the same is true for most gear types. Overloading during the initial break in phase is not good for your gears, running extended break in periods does nothing. Once the gears have broke in they are broke in and no amount of directed break in procedures can change the gears from what you made them when they were actually in the break in period.


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