Gear Break in...umm this is new..??

[whyask]

Ok so I pick up my baby today from the shop for the 3:90's that went in.. and they hand me this letter/ "follow this" paper..

"All new gear sets require a break- period to prevent damage from overheating. After driving the first 15 or 20 miles you MUST let the differential cool for 30-40 minutes before proceeding. Drive the first 500 easy miles and then change the oil after the first 500 miles."

This is a new one, Ive had gears in all 4 stangs Ive owned and this was the first time Id seen this...

ANY THOUGHTS..
Thanks
Justin

 

[Smeech]

I was told the same thing when I got my 4.10s from Apex Motorsports.

 

[Duke309]

I drove about 100 miles before really getting on it with my gears and they are perfect. Most people dont even wait to beat on em with no issues. If you really want to be safe I guess do all that.

 

[whyask]

Ya it seemed a bit extreme..I can understand about the changing of the gear oil, that makes since and its true...but the 15 minutes and cooling..ya NO..mayby with 4:50+

 

[thomas91169]

i wouldnt. just drive them normal, let them break in to your style. i mean of course, dont do a burnout out of the shops parking lot.

 

[BurningRubber]

Well so far, how are the 3.90's? Im considering them.

Ive heard of doing the heat cycle. Let them warm up to a normal, shorter drive, let cool and then repeat once or twice more. Then your good to go. Thats what ive read, no personal experience.

 

[whyask]

i love em...still not used to , I had 4:10's but with the new engine and the KB 2.6 going I had to drop down to something lower...But over all at Highway in 5th gear, I can still chirp them..I hit around 2300 on the highway at 80-85..not bad
(still really dont use first gear) hahaha

 

[san~man]

My mechanic has been doing gears forever and I asked him about "break in" when I picked my car up from him after the 4.10's went in.

His words...."none." Still going strong almost 6 years later.

 

[eagleautosports]

When I had my gears put in, I left two stripes out of the driveway. 13 years and never any problems. Might be a good idea about the heat cycle, can't hurt to do it.

 

[whyask]

sanman with the words of wisdom ...."NONE" i like it..haha,

I did the heat cycle anyways today, my work was about 15 miles away, I needed to get my bags so the car sat for about 30 minutes , BUT after that, I hit the highway floored to the ground...

Still gonna change out the gear oil after the first 500 miles or so, just cause of all the new shavings and what not in the oil...never hurts..

 

[Mike97gt]

I broke my 4.10's in with a 3k RPM launch and a couple 1-2 2-3 powershifts right after I finished installing them.

 

[LaserRed01GT]

I hear a lot about this all the time. Some shops will even run the car on the lift for a while with no load on the gears and then let them completely cool. The gear manufacturers just recommend a break in for a legal disclaimer I think.

Break 'em in with a nice healthy burnout.

 

[Give Me TP]

I never changed the rear end lube in my car since going to FRPP 4.10's three years ago, and didn't follow any specific break-in procedure. No negative issues yet in over 30K miles.

 

[steveb24]

my performance shop said theres no such thing. so there isnt!

/thread

 

[bakos24]

The guy that did my gears told me to stop after so many miles and let cool down before driving again. I just went easy on it for a while just to be safe.

 

[sgarlic]

I'm thinking since there's so many people who have basically proved that a break-in period isn't required, my guess would be that they just say that so if you come back with busted gears right away, they have something to blame the breakage on, instead of having to admit that perhaps they did the installation wrong.

Add me to the list of people who peeled right out of the parking lot after my 3.73's went in. No break in. Thousands of miles later, doing fine.

 

[04YELLOWGT]

Never broke in mine. Drove 15-20 miles home and went WOT atleat 4 times. Then did it about 10 more times that night.

 

[whyask]

Hell ya guys ..thanks for all the input

 

[HoustonGT]

I simply drove it a bit easy the first few hundred miles because im a broke ass college student who can't afford to fix crap. better safe than sorry but i don't think its completely necessary

 

[lexluthr69]

Sounds like everyone's an expert here on gear break in, because they ripped on their new gears and didn't break anything. LOL

Here's a good rundown by Amsoil on why it's a good idea to "break in" your gears.

http://www.upmpg.com/lubricationnews/differential_maintenance/

To me, it's saying that the break in period is the highest temps your axle will see. That's enough for me to not want to see what stress the gears are capable of, when I haven't even had a chance to set the wear pattern on 'em.

Every gear set I've ever bought and installed, I've broke in. /shrug