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corsair23
11-13-2009, 12:02 PM
Ok...I'm probably overthinking this but I'd rather be safe than sorry :hill:

Gear break procedure per my gear maker states:

BREAK-IN PROCEDURE: (IMPORTANT!!!)

In order to prevent damage to the differential it is essential to follow break in procedure following installation of a new ring & pinion. New Ring & Pinions will generate more heat initially after installation and can cause gear oil to break down, leading to premature failure. On your first drive, stop after the first 15 or 20 miles you and let the differential cool for 20-25 minutes before proceeding. Drive conservatively for the first 500 miles following installation (avoid hard acceleration & towing). After completing standard break-in, tow for very short distances (less than 15 miles) and let the differential cool before continuing during the first 45 towing miles. Change the gear oil after the first 500 miles. This will remove any metal particles or phosphorus coating that has come from the new ring & pinion.

Premature overloading/overheating will cause gear oil to breakdown, and may result in parts failure.



Ok...I've got may 80 miles on the new gears...Maybe 20 highway miles and the rest city. I need to make a trip out to the airport today and also to Conifer this weekend. That will be a fair amount of highway driving which I am assuming will get the gears really warm/hot.

Any concerns that would warrant taking the 80 instead on these trips or just get in and go??

AxleIke
11-13-2009, 12:10 PM
Ok...I'm probably overthinking this but I'd rather be safe than sorry :hill:

Gear break procedure per my gear maker states:



Ok...I've got may 80 miles on the new gears...Maybe 20 highway miles and the rest city. I need to make a trip out to the airport today and also to Conifer this weekend. That will be a fair amount of highway driving which I am assuming will get the gears really warm/hot.

Any concerns that would warrant taking the 80 instead on these trips or just get in and go??

Assuming you did the standard break in as described, and the gear install was done correctly. you should have zero trouble. Get in and go.

Change the diff oil at 500 as stated.

Uncle Ben
11-13-2009, 12:50 PM
drive that sucker!

timmbuck2
11-13-2009, 12:53 PM
You can drive it, but you REALLY need to make sure to be extra careful....drive ONLY in reverse and do NOT turn your lights on under ANY circumstances....and ONLY make left turns.

Or just do what Uncle Ben says. :)

corsair23
11-13-2009, 12:54 PM
Thanks guys...I figure I followed the break-in procedure about 10 times now because all of my drives have been relatively short...Started wondering if maybe my drives have been too short and that the gears didn't heat up to what they should and then cool...As you know I'm one of those that likes REAL explicit instructions :hill:

Like: First drive MUST be 15-20 miles at X speed then stop and let the gears cool for X minutes. After that, normal driving but no towing for the first 500 miles. :blah: :blah:

nakman
11-13-2009, 01:29 PM
If you follow that procedure to the letter you will likely be the first one, ever. Read the fine print again..

more heat initially after installation and can cause gear oil to break down, leading to premature failure.

So if you want to worry excessively, then drop your cheapo break-in gear oil one more time after a couple hundred miles. Removing the "broken down" oil removes your exposure to risk right?

When I did my gears, I had to leave town for a week right after. Then it was one week before Moab... I managed to get 200 miles on those gears before I swapped gear oil, then promptly proceed to pull the camper to Moab and wheel for a week. :) 45,000 miles later, all is well...

wesintl
11-13-2009, 01:31 PM
LOL, I can't get my mind out of the gutter

DaveInDenver
11-13-2009, 01:45 PM
When I picked my truck up from Christo's with new gears I drove home taking it easy, about 30 minutes. The axle was really hot and let it cool overnight. I commuted the next week trying to engine braking a lot to get the coast side faces worn. The axle never got nearly as hot as that first trip. Drained the oil the next weekend and just regular maintenance since. I think the real key is to drain the break-in oil pretty soon after the initial miles, there was a decent cone of very fine pixie dust shavings on the magnet and the heat is probably not good. I figure it's all about the set-up, the gear faces are going to find their happy points really quick and the major tempering it going to be done after that first cool-down.

Uncle Ben
11-13-2009, 01:48 PM
When I picked my truck up from Christo's with new gears I drove home taking it easy, about 30 minutes. The axle was really hot and let it cool overnight. I commuted the next week trying to engine braking a lot to get the coast side faces worn. The axle never got nearly as hot as that first trip. Drained the oil the next weekend and just regular maintenance since. I think the real key is to drain the break-in oil pretty soon after the initial miles, there was a decent cone of very fine pixie dust shavings on the magnet and the heat is probably not good.

Heat is normal during break in! Friction is highest until the wear pattern (polished patch) gets established. Both bearings and gears need to seat.

DaveInDenver
11-13-2009, 01:51 PM
Heat is normal during break in! Friction is highest until the wear pattern (polished patch) gets established. Both bearings and gears need to seat.
Yeah, I know.