Gear/diff break in?

[1fastsedan]

So I'm finally going to bet around to installing my 09 Getrag diff in a couple of weeks. I was wondering what you guys are doing for break-in and what gear oil are you using. I talked to my local gear/axle shop and the owner said to run dino oil in a high performance car. He said that the synthetic can't handle the pressure like a dino oil.

Below are 3 break-in procedures that I found on-line. Any thoughts? Which one does Richmond recommend with their gears?

1. Upon differential installation, and fluid top off, proceed to drive vehicle to a controlled
area where several circles/figure eights can be performed. Drive vehicle (at idle speed) in
20 figure eights, full lock to full lock. Then drive (at idle speed) in 20 full lock circles
left, 20 full lock circles right.
All Diffsonline differentials (excluding Kaaz LSDs) require a 1200 mile break in period.
Do not exceed speeds of 85mph as bearings may overheat. Drive vehicle moderately
without extreme load differences such as shocking (hard shifting with swift clutch use).
After 1200 miles, change oil in differential with recommended fluids.

2. Use only high quality name brand gear oil and fill the differential until the oil spills out the plug hole. Positraction carriers require anti-friction additive.
All new gear sets require a break-in 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 500 easy miles before towing. 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 gear set.

3. After installation, fill the differential with only premium national brand 80w90 or 85w140 GL-5 gear oil. Also add 4-8 ounces of Dane Spicer friction modifier to the oil if your differential contains a limited-slip or posi unit. Alert: Verify that the drain and fill plugs are properly secured.
-Drive your vehicle easy for 30 minutes or approximately 20 miles. Avoid aggressive starts, hard stops and long distances at a steady speed.
-Let the differential cool for 15-20 minutes.
-Repeat steps 2 and 3 for 1st 100 miles.
-It is not recommended to tow or use WOT during the first 500 miles.
-When towing for the first time, drive easy for 20 miles let the differential cool for 15-20 minutes.

It is recommended to change the differential fluid at 500 miles. Use the lubricant specified in step 1. Subsequent oil changes should be performed every 20,000-30,000 miles.

Many differentials have been damaged by overheating, overloading, inadequate or improper lubrication. The above procedures may be a minor inconvenience, but if followed, your differential should prove to be one of the most dependable devices in your vehicles.

[budoboy]

I doubt Chrysler recommends any break in. I can't imagine a dealer telling a customer to do any of the above on their new car w/ the same diff.

[dudeiwin86]

i got my getrag and it had gear oil in it.
i drained the bitch,
filled it with mobil 1 75w90 LS synthetic gear oil (LS is for limited slip) til it spit out the side filler hole
plugged it
installed it

beat the **** out of it on the road right afterwards and am still loving it

maybe ill drain it soon and refill it after 1000 miles, maybe not..

did i do it the right way?
shrug

[1fastsedan]

I doubt Chrysler recommends any break in. I can't imagine a dealer telling a customer to do any of the above on their new car w/ the same diff.

Yeah, but new cars have break-in recommendations for the engine, which would take care of the diff too.

[budoboy]

Yeah, but new cars have break-in recommendations for the engine, which would take care of the diff too.

True enough. So basically drive 500 miles without full-throttle starts. I drove about 150 miles to and from my shop (had to go back because of rear end rattle caused by loose shock bolts) and have been to the track twice since then. Seems to work just fine.

My installer said if I felt like it I could have the fluid replaced after a 1000 miles.

[dudeiwin86]

everything ive ever heard, especially regarding new cars is that...

after like 5 minutes of driving its broken in,
its all about seating the rings and thats the only thing that you really need to be concerned about "breaking in"

im no pro, just what i hear.

a rear diff may be different... more gears and what not.

there was actually some shavings on my magnetic drain plug for the diff when i drained it.

[slideway]

I think I heard some shops used to run in new or rebuilt rear end's on the jack stands for a few minute's After installing them. I doubt it's needed though.

[Maistro69]

beat the **** out of it on the road right afterwards and am still loving it

maybe ill drain it soon and refill it after 1000 miles, maybe not..

did i do it the right way?
shrug

Sounds like the way I think. Ever notice how the stuff you baby and try to treat right will do you wrong everytime, and the sh!t you beat the hell out of just says give me more is that all you got. A few girlfriends come to mind LOL

[InferAl]

I was told a few heat and cool cycles, I may have got that and it rained the whole rest of the day so when I was playing around they were just spinning real easy no stress.

So maybe I got a little break in but the next day I wasn't so easy on it

[mrjoecool]

Sounds like the way I think. Ever notice how the stuff you baby and try to treat right will do you wrong everytime, and the sh!t you beat the hell out of just says give me more is that all you got. A few girlfriends come to mind LOL

dude you made shoot coke out of my nose laughing so hard (a few girlfriends come to mind)lmfao

[mikespy]

When my new getrag went in the car i reversed it outta the shop straitened her up and lit that MOTHERFKR up!!!

[1fastsedan]

OK, I did a little more research. It appears that the following is for an ENTIRE NEW clutched differential.

Upon differential installation, and fluid top off, proceed to drive vehicle to a controlled
area where several circles/figure eights can be performed. Drive vehicle (at idle speed) in
20 figure eights, full lock to full lock. Then drive (at idle speed) in 20 full lock circles
left, 20 full lock circles right.
All Diffsonline differentials (excluding Kaaz LSDs) require a 1200 mile break in period.
Do not exceed speeds of 85mph as bearings may overheat. Drive vehicle moderately
without extreme load differences such as shocking (hard shifting with swift clutch use).
After 1200 miles, change oil in differential with recommended fluids.

Then the procedure below this is for when installing new gears on a used differential.

Use only high quality name brand gear oil and fill the differential until the oil spills out the plug hole. Positraction carriers require anti-friction additive.
All new gear sets require a break-in 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 500 easy miles before towing. 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 gear set.

[budoboy]

OK, I did a little more research. It appears that the following is for an ENTIRE NEW clutched differential.

Upon differential installation, and fluid top off, proceed to drive vehicle to a controlled
area where several circles/figure eights can be performed. Drive vehicle (at idle speed) in
20 figure eights, full lock to full lock. Then drive (at idle speed) in 20 full lock circles
left, 20 full lock circles right.
All Diffsonline differentials (excluding Kaaz LSDs) require a 1200 mile break in period.
Do not exceed speeds of 85mph as bearings may overheat. Drive vehicle moderately
without extreme load differences such as shocking (hard shifting with swift clutch use).
After 1200 miles, change oil in differential with recommended fluids.

Then the procedure below this is for when installing new gears on a used differential.

Use only high quality name brand gear oil and fill the differential until the oil spills out the plug hole. Positraction carriers require anti-friction additive.
All new gear sets require a break-in 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 500 easy miles before towing. 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 gear set.

No one with a brand new '09 Getrag-equipped car is going to do all this (and won't be told to by Chrysler) and I doubt all these cars are going to have differential failures as a result.

[slideway]

1fastsedan, I thought you made up a funny joke till I got to the end and there was no punch line!

[1fastsedan]

1fastsedan, I thought you made up a funny joke till I got to the end and there was no punch line!

If you saw the burned up Getrag diffs out of some Chevy's that were at the diff shop, you'd know why I'm concerned about doing it right.