What are the Do's and Dont's after new gear install.

steve_r2

New member
As this is the first time I have re- geared what are the Do's and Dont's I need to do ? Being a total noob to this.
JK 09 Auto 4 door being fitted with 4.88s
I have read it somewhere but can not find it again.
After the first 100 miles is it ok to do some light wheeling or do I have to wait for the full 500 miles and check ?
Appreciate any help.
 

cozdude

Guy with a Red 2-Door
i would wait at least the first 500 till you even put it in 4hi. thats what i was told by my installer. so no off-roading till then. also be very easy on the throttle the first 500. give the gears 4-5 good heat cycles, so drive say 15-20 miles then sit and let your axles/gears cool down for at least an hour before going another 15-20 miles. i personally did almost 10 heat cycles before i went for a longer distance drive.
 

pastorwug

New member
After the install at ORE Drew told me to make sure I don't go over 55 mph as I had to drive 200 miles home. I stopped several times along Malibu Hwy 1 and took a leisurely time. He said absolutly no towing for the first 500 miles.
After the gear oil change at 500 miles he said do anything I want - and so I have - rock climbing, fire roads, towing, etc. and they are wonderful.
He said the big key is go slow, no towing, no offroad for 500 miles.

I went from 4.11 to 5.13s
 

wayoflife

Administrator
Staff member
As mentioned, go easy on the gas for the first 500 and then do a open over differential inspection and oil change. I wouldn't worry so much about shifting into 4HI but, would make sure to still go easy on things.
 

jkuone

New member
I've got 130 miles on since I re geared, taking it easy all good so far.hard to refrain from playing with new ARB locker in rear but I will till broke in...
 

wayoflife

Administrator
Staff member
I've got 130 miles on since I re geared, taking it easy all good so far.hard to refrain from playing with new ARB locker in rear but I will till broke in...

LOL!! You can turn it on and off but, I wouldn't put it to the test just yet. :D
 

Elusive

New member
There's no magic in gears. The factory doesn't run gear sets before cars go out (though they do say to break in engine). Gears are made of very hard steel alloy and when properly set up require no break in period. Many many times I've set gears up and we wheeling immediately. Most gear manufacturers only tell you to do a heat cycle before any shock loads.
Make sure the gears are set up properly. Run them down the highway till they get good and warm. Go home and change the gear lube and inspect the ring gear bolts (especially with an ARB). That's it.
 

jeepgreenjon

New member
There's no magic in gears. The factory doesn't run gear sets before cars go out (though they do say to break in engine). Gears are made of very hard steel alloy and when properly set up require no break in period. Many many times I've set gears up and we wheeling immediately. Most gear manufacturers only tell you to do a heat cycle before any shock loads.
Make sure the gears are set up properly. Run them down the highway till they get good and warm. Go home and change the gear lube and inspect the ring gear bolts (especially with an ARB). That's it.


I am going to have to respectively disagree with you on this one. Gears do require work hardening, new gears are lapped at the factory however the lapping pressures at the factory come nowhere close to the pressures that apply to them while driving. All gears factory or not need to be work hardened, we went over all of scientific reasons in trade school and I can pull out my text book if you wish. However the long and short of it is, yes all gears need a break in period, period.
 

Elusive

New member
I am going to have to respectively disagree with you on this one. Gears do require work hardening, new gears are lapped at the factory however the lapping pressures at the factory come nowhere close to the pressures that apply to them while driving. All gears factory or not need to be work hardened, we went over all of scientific reasons in trade school and I can pull out my text book if you wish. However the long and short of it is, yes all gears need a break in period, period.

I agreee that gears get work hardened but they also do not need more than a single heat cycle to do it.
When you drive only 50 miles the pattern will already be apparent of the teeth and the lapping will be (mostly) complete.
taking it easy for months or skipping wheeling trips because your gears are new is foolish.
 

wayoflife

Administrator
Staff member
Make sure the gears are set up properly.

Really? And exactly how does an average Joe do that?

...taking it easy for months or skipping wheeling trips because your gears are new is foolish

It takes you months to put on 500 miles on your odometer?

As foolish as it may be to skip a wheeling trip, I personally find there to be NO HARM in following the recommended break in procedure provided by your shop. For your benefit, I personally would recommend that you follow it just in case. Being that it you'll be spending $1000 or more to regear, why take chances? At least, that's how a fool like me sees it. Of course, it's your Jeep and you can do what you want with it.
 

Elusive

New member
Really? And exactly how does an average Joe do that?



It takes you months to put on 500 miles on your odometer?

As foolish as it may be to skip a wheeling trip, I personally find there to be NO HARM in following the recommended break in procedure provided by your shop. For your benefit, I personally would recommend that you follow it just in case. Being that it you'll be spending $1000 or more to regear, why take chances? At least, that's how a fool like me sees it. Of course, it's your Jeep and you can do what you want with it.

New gears fail because they overheat while they are lapping. Thats why most gear manufacturers recommend driving up to 300 miles before TOWING. Theres no chance of overheating gears rock crawling so if the lapping is done there is no reason to wait any longer.
The average joe can't ensure his gears are set up propery other than having a quality shop install them seeing if they make noise but no amount of break in will fix that.
 

wayoflife

Administrator
Staff member
The average joe can't ensure his gears are set up propery other than having a quality shop install them seeing if they make noise but no amount of break in will fix that.

My point exactly. The average Joe can't ensure his gears are setup properly. The best he can do is take it to a quality shop to have them installed and most of those will have a specific break in procedure. Of course, after spending over a thousand dollars to have the work done, it would be foolish to follow it. :naw:
 

jeepgreenjon

New member
New gears fail because they overheat while they are lapping. Thats why most gear manufacturers recommend driving up to 300 miles before TOWING. Theres no chance of overheating gears rock crawling so if the lapping is done there is no reason to wait any longer.
The average joe can't ensure his gears are set up propery other than having a quality shop install them seeing if they make noise but no amount of break in will fix that.

No chance in overheating gears while rock crawling!? I would have to say rock crawling would be just as hard on gears as towing. Shock loading would come into play I would think but I could be wrong...
 
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