? Break in time/mileage and best practices for new ring and pinion gear?

[biomedtechguy]

I am (or possibly was) hoping to get my 3.54 ring and pinion gear swapped OUT and a new Dana/Spicer 4.10 installed in time for my car club's annual track day November 19th. My amazing Passon a855 5 speed has paved the way for me to have the benefits of the 4.10 yet I will still be turning 700-800 less RPMs in 5th than I used to turn in 4th with the 3.54. This is my parts list:
OEM Spicer 4.10 ring and pinion $285
Master bearing install kit Timken USA $150
OEM Spicer Power-lock clutch pack $79
Timken USA Set 7 wheel bearing kit includes inner steel gasket, outer foam gasket and inner and outer seals $95
The concern is that my mechanic is concerned about the break in time/mileage.
I'm thinking dedicated track cars change ring and pinion gears, and what kind of break in process can they possibly have that I can't do better than, even in a short period of time, since I drive my car on the street and highway.
Advise please? Thanks.

 

[moparnation74]

Advise....it is a dana...do not worry about that....

The key is..is it properly setup....and the fluid with friction modifier...

 

[PP1RT]

Drive it for some short drives(5-10 miles) and park to let it cool down in between. After a few cycles dont worry about it.

Track cars generally drive a short distance and park between races.

 

[biomedtechguy]

Advise....it is a dana...do not worry about that....
The key is..is it properly setup....and the fluid with friction modifier...

It will be properly setup, this mechanic knows his craft and I have seen him evaluate and repair a problem on my car as well as know within a minute whether I had a coarse or fine pitch type ring and pinion. He owns a 4x4 shop, but has some really nice muscle cars there too, and did a great fast thorough job on what I had him address on my car. I know about the friction modifier (used to be called sperm whale oil derivative). What rear end gear oil brand type and weight do you recommend? South Louisiana.
Thanks for the replies!

 

[moparnation74]

It will be properly setup, this mechanic knows his craft and I have seen him evaluate and repair a problem on my car as well as know within a minute whether I had a coarse or fine pitch type ring and pinion. He owns a 4x4 shop, but has some really nice muscle cars there too, and did a great fast thorough job on what I had him address on my car. I know about the friction modifier (used to be called sperm whale oil derivative). What rear end gear oil brand type and weight do you recommend? South Louisiana.
Thanks for the replies!

Oil now that will bring a lot of opinions...

I use what Dr Diff uses and recommends Wal Mart Supertech 85-140. And the friction modifier he uses.
http://www.doctordiff.com/friction-modifier.html

We deal with the same temps in TX here...

 

[biomedtechguy]

Oil now that will bring a lot of opinions...
I use what Dr Diff uses and recommends Wal Mart Supertech 85-140. And the friction modifier he uses.
http://www.doctordiff.com/friction-modifier.html
We deal with the same temps in TX here...

Since I'm buying the parts from Cass, I will use what he (you) recommend. Thanks again.

 

[bm02tj]

If you have a good gear man do what he tells you

 

[747mopar]

Since the bearings are preloaded slightly I feel it's a good idea to start out with short drives to minimize heat buildup but they should break in pretty quickly. Like everyone is saying, take your builders advice or Dr Diffs.

 

[Budnicks]

Let it heat cycle a couple times, get it warm & let it cool...
I'd also do some forward & reverse,
with some sharp turns in a parking lot
or somewhere both ways left & right {for the diff.} etc.
again a couple times let it heat cycle,
make sure no strange noises or too much backlash,
check the oil after it cools down, make sure it's topped off...
IMO then should be good to go, always worked for me...

Racing Pro-Gears are really soft gear so not to be brittle
IMO a bit of a different animal
I'd put the car on jack stands run it long enough
to get the oil warm, forward & reverse,
then put it on the ground & it was pretty much ready to go
or just drive it around a bit in the pits, get temps up
they were usually spools, not a differential or clutch pack etc.

 

[biomedtechguy]

Thanks again for the replies. Thanks Budnicks for the advice and the description of the difference between race gears and race prep and street gear prep.
Tomorrow will tell. I am going to go ahead and get my "list" shipped from Dr. Diff once I check it against my mechanic's recommendations. If my mechanic thinks I can break it in in time, I guess I'll be driving my Roadrunner some before track day.
On a side note, my best run last year was 13.35 at 106. I power shifted for the first time and did a good job imo because I wasn't bouncing off the rev limiter between gears. Even with my 315/35/17 Toyo Proxes TQ Drag radials I have to come off the start easy on the throttle, but the moment I'm rolling I can stomp it.
I am changing out the master cylinder that came with the front disc brake conversion kit because the black plastic 4 bolt reservoir caps keep leaking. I'm getting the 4 bolt one piece metal cap iron reservoir to replace it until the day I get a Wilwood front and rear disc brake system with larger rotors, now that I have 17" wheels-I want to take advantage of that. The point is I am installing a line lock so I can heat the drag radials beyond just spinning them in the box as the car moves forward. I always avoid the water too. The 292* .509 lift purple stripe cam and CompCams springs, hydraulic flat tappet lifters, 10* locks, and retainers have noticeably improved 4,500-6k performance (my original springs were "tired"). I'm CERTAIN that I have a 12 second car, it's just a matter of doing my part tuning and driving it to get it there. I am also going to try a couple of runs shifting out at 5,200-5,400 instead of 5,800-6k just to see if my ET drops. I will follow up in a new thread after track day, and hopefully I'll have my new 4.10 broken in and ready to go for track day.
Thanks again guys!

 

[Cranky]

Even factory new cars do not get much run time on the gears before they get sold to the public and they survive. I know they used to get a good test run before leaving the plant and not much else after that before being sold. I like to do a couple of drives before hammering them but on a track car, about all you can do is drive it at the track if it's not street legal. If you think you still will not have enough run time before going to the track, try to get there early enough to make a couple of easy passes during time trials and drive it all the way to the end of the shut down area. That should put some heat into them during each pass to help with break in.

 

[biomedtechguy]

So far I have only been to the track once a year, for my club's track day. Busy with work and honey-do list...hoping to start going more often like I used to. A friend has a car he is running on test and tune nights, so there's a good chance I'll be going more often.
Point is driving on the street is 95% of what I do, so break in on the street is no problem. I'm driving to the track too, a little less than 1 hour away.

 

[stage3]

The concern is that my mechanic is concerned about the break in time/mileage.
I'm thinking dedicated track cars change ring and pinion gears, and what kind of break in process can they possibly have that I can't do better than, even in a short period of time, since I drive my car on the street and highway.
Advise please? Thanks.

I am going thru the same thing..my new dana 60 4.56 gear set came with instructions..and advised by the mechanic at rear end speacialty's in san jose ca...break in miles are 500..15-20 miles at a time ,, no getting on it,,do not go over 50 mph,,then pull over for 30 minutes to let the oil/gears cool..rinse/repeat...500 miles!im at 385 now..at 500.change the oil..and go..

 

[Cranky]

Gears break in a lot faster than that. The guy is just trying to make sure you don't come back complaining about something....

 

[PP1RT]

I am going thru the same thing..my new dana 60 4.56 gear set came with instructions..and advised by the mechanic at rear end speacialty's in san jose ca...break in miles are 500..15-20 miles at a time ,, no getting on it,,do not go over 50 mph,,then pull over for 30 minutes to let the oil/gears cool..rinse/repeat...500 miles!im at 385 now..at 500.change the oil..and go..

500 mile warranty then?? 50 miles are more than enough baby time...

 

[biomedtechguy]

These are the parts Dr. Diff offered, and if they are needed/make sense, here ya go.
To recap:
OEM Spicer 4.10 ring and pinion $285
Master bearing install kit Timken USA $150
OEM Spicer Power-lock clutch pack $79
Timken USA Set 7 wheel bearing kit includes inner steel gasket, outer foam gasket and inner and outer seals $95
Now I don't see how there can be much if any break in difference between THIS PARTICULAR parts list and what Ma Mopar installed on the assembly line, and I don't recall break in time specified for anything other than the motor and maybe clutch disc. There was a break in process for my a855, but that is satisfied now.
I will try to strike a balance between what I've read here, but since Cass and my mechanic are the two who I would have to notify in case of a problem, I will have to give some weight to what they say too.

 

[moper]

With street gears - I always run them on jackstands for 15 minutes at 20-50 mph. Let it cool completely (overnight). Drive it lightly for 5-10 miles of mixed driving with no hard accelerating and lots of coasting/ gear braking deceleration. Let it cool 100% (overnight). If it's all quiet during the 2nd heat cycle, it's good to go.
Pro gears - go race it.

 

[biomedtechguy]

I spoke with Cass (Dr. Diff) and my mechanic who is doing the ring and pinion install. Parts will arrive Wednesday, car to the shop Wednesday, and I will be able to drive it around locally to break it in in time for track day.
Given that my motor is basically a stock "heavy rod" 440, with a 292* .509 purple stripe cam and lifters/springs/locks/retainers that are appropriate, 1 7/8" primary headers, and the 6 bbl setup, what kind of reduction in 1/4 mile ET should I expect going from 3.54 to 4.10, best guesses ok?

 

[Cranky]

Maybe 12.90's? Hard to say really. If traction is still good, it's possible.

 

[oldbee]

Without slicks it's real hard to guess what kinda times you'll get. Wheel spin is a given, question is for how long.

 

[1967coronet440]

Strange says 500 mile break in period on my new S60