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Question on "new gear" break-in.. Different scenario.

If I have a LP front axle and a HP rear axle, should I spend the first 20 minutes driving in Reverse to maximize my break-in efforts?
 
I broke my gears in with a nice smokey burnout followed by lots of full throttle...
 
vetteboy said:
I spent 20 minutes stuck in traffic today going a mile and a half.

Also spent 20 minutes completing a lap at the woods race I was in this weekend, which I'm sure was far more abusive.

So I'm assuming that's 20 minutes of continuous somewhat-gentle, constant-speed driving. There are zero roads around here that I can accomplish that on and I'm certainly not trailering it to someplace that I can.

I would also say that starting in the dead of winter vs. the heat of summer plays a part, the gears will definitely take longer to heat up if the gear oil's sittin at 0 degrees.

What does getting the gears to an arbitrary (and unknown) temperature have to do with the lapping process? Is there a critical temperature where lapping becomes more effective?

:dunce:

500 miles of holding back your right foot, change the oil, down the road.
Click to expand...
It's not about getting it up to any particular temperature. It's about keeping it from getting above a certain temp (do not know the magic number, it probably depends on what kind of oil is used and a number of other factors). As was stated before, the object is to prevent the breakdown of the gear oil mas well as overheating the ring and pinion and changing the heat treatment of the metal. All of is this is just precautionary. It may very well not be an issue if you don't do a break in but if you don't it could very well be. It's about better safe than sorry.
 
NattyBoh said:
What about thus guys. Being 4 wd how does the front gears lap? I'm guessing since the front is always spinning its still in contact, right?
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If you put new gears in and drive around in 2WD the front gears will lap in over a much longer period of time. The resistance of the front driveline puts a very light load on the gears while driving but it is on the coast side of the gear teeth. Gears don't tend to get hot under slow 4 wheeling conditions so a trailered wheeling rig would not need a break in unless it is to be used at high speed like jeepspeed conditions.
 
foxwar71 said:
If I have a LP front axle and a HP rear axle, should I spend the first 20 minutes driving in Reverse to maximize my break-in efforts?
Click to expand...
If you choose this method you have to get a front mounted hitch and tow a heavy load in front of you to apply the correct force to the gears during break in and stop to cool every 18 minutes 20 seconds. :D
 
Hey jeeperjohn you know you can multi-quote right? :D
 
RWK, I was talking about professional race motors, not sportsman race motors. Every NASCAR, Indy, or F1 motor is broken in on the dyno so the team knows what motor makes the most power befor they put it in the car. Which is to be used for the backup and primary motor. Now top fuel motors aren't because they wouldn't survive the break in period anyways and low budget, local, sportsman racers don't because they don't have the budget. But every top level professional race team does.

Hijack complete.
 
here's my take for what its worth....as someone who has set at least a few dozen r&p's.....

hopefully this will end the debate:

Break-in period for new R&P?

It couldn't hurt, and it might help.
 
Well no matter what a few people, that have no position or qualifications in this matter, say.

I will continue to recommend what the gear company recommends.

But you all can do what ever you like, as stated. Its your money.

Keep this in mind...
Most of you have a D60 and or a 14T (as do I). And the ring gear to pinion contact patch is about 400% larger then the D30/D44/D35 that 99% of the XJs have. And those D60/14T R&P are designed to reliably and daily, occure loads and heat levels from rigs that are 2-3 times the weight and at the same time have about 4 times the Torque fed to them.

SO comparing the D60 and 14T or even a F8.8 to what most of the population here is asking about, is like comparing a mini cooper to a Escalade...

I am amazed at how many people here are so much more, qualified in gears then any of the gear companys, when it comes to gears...

What else are all you more qualified at, then the engineers and R&D personel of companies that produce parts? I sure would like more insight as to correct methods and means, I mean you all should open your own companies. You seem so much more intellegent and qualified then the ya-whose running them now...
 
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MoparManiac said:
I'm pretty sure Chris (vetteboys) rig weighs as much as a fullsize and puts down way more torque.

:laugh:
Click to expand...

new diesels are mostly all around or over 6000 lbs curb weight and make on the order of 750 Ft.lbs. If there is a jeep on here weighing 6000 lbs and putting over 600 ft lbs to the wheels, I will both be very impressed by their engine build and confused on why they used 2" solid bar to build their cage
 
Hoooper said:
new diesels are mostly all around or over 6000 lbs curb weight and make on the order of 750 Ft.lbs. If there is a jeep on here weighing 6000 lbs and putting over 600 ft lbs to the wheels, I will both be very impressed by their engine build and confused on why they used 2" solid bar to build their cage
Click to expand...

Chris's rig has an internal and external cage (due to redesign) with plating and heavy gauge steel all over the place. I'd say he's a few hundred shy.

And you're missing the whole concept of GEARING.

He has a 4.6 stroker, NV4500, going into a 231/300 doubler.
 
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