: New rear end is in, break in?



TTJR-CTS-V
04-19-05, 04:31 PM
Well the boy's at the Cadillac dealer replaced the rear end on my 05 last week! No whine sound and no oil drips on the garage floor(yet). What type of break in should I be doing with the new rear end?

CTSV05
04-19-05, 04:43 PM
Do as many full throttle clutch dumps, and as many hard full power shifts as humanly possible.

Drive at more then the recommended speed limit for extended periods of time.

(pleasedisregardallabovestatementsastheyareforthea musementofthemanywhohavenotfollowedproperbreakinpr oceduresinthepast)

V-seriesTech
04-19-05, 04:47 PM
Do as many full throttle clutch dumps, and as many hard full power shifts as humanly possible.

Drive at more then the recommended speed limit for extended periods of time.

(pleasedisregardallabovestatementsastheyareforthea musementofthemanywhohavenotfollowedproperbreakinpr oceduresinthepast)



:bonkers:

urbanski
04-19-05, 05:50 PM
beat it and beat it hard
i haven't seen any correlation between diff life and "break-in"
in fact i think i recall more failures with folks who "babied" it.
oh, but do change the diff fluid at 500 miles :)

StealthV
04-19-05, 05:58 PM
Early in gear life it is good to put them through many heat & cool down cycles as practical before driving any real distance.

Drive vehicle approximately 10 miles at normal speeds while accelerating and decelerating several times conservatively, then let cool for one hour (or overnight).

Repeat this cycle several times.

Keep increasing the torque load on each heat/cool cycle to work harden the gears. The secret to all this is proper cool down between cycles.

Agree with Urb - dump the fluid early and remember the additive upon refill.

dannystang
04-19-05, 06:35 PM
Hmm well my 1st rear had 500 miles of demo, soo I will total throw that one in the wind.

My second rear was REAAAALY babied with the above procedure after asking here. Well actually I drove city streets for 650 miles, then started on expressways lightly then a little harder.

I am at 1400 miles. The new rear goes in tomorrow.

Hmm...

Vrocks
04-19-05, 06:53 PM
Here's what I did, and my diff is perfect at 13,000 miles, and I haven't replaced the fluid [ was told it should last 50K - 100,000 miles ]:

First 400 - 500 miles = Conservative driving, slow to normal acceleration, varied speed, downshift as smooth as possible. The average driving time was as about 25 minutes, with several hours of cool down time.

Around 500 miles I did a full throttle roll on through 1st, 2nd, 3rd, and 4th gear.

After 1,500 miles I did a launch once in a while, with frequent full throttle useage once the V was rolling. Since then, I've launched the V many more times and things are still fine.

I've experienced very minor hop in dry conditions during a launch, and several times when the roads were wet. I've only experienced hop on a 1 - 2 shift 1 time, so I [now] believe the wheel hop may be the biggest culprit in rear end failure.

Dave's V
04-19-05, 08:00 PM
I was told by a Cadillac mechanic that they can download the car's computer to see how you broke in the axle. They were about to give me crap when my first rear end failed at 1000 miles, until I told them their sales department put the first 661 miles on it. It was fixed within a week.

500 miles of breaking it in per Cadillac instructions plus 1000 more miles and a fluid change to redline, it is silent as well a new car should be.

I have heard people have problems taking it easy or treating it like it is a rental. Likewise, I heard people not have any problems both ways. I'm beginning to wonder if it is bad batch of rear ends from Getrag. Makes me wonder since they are German along with 2 of the Vs main competitors.

dannystang
04-19-05, 09:47 PM
Umm, where exactly are the cadillac instructions online?

I'm going to video-tape my new rear end for the first 1000 miles.

CTSV05
04-19-05, 09:58 PM
Well, we just drove our car like we wanted to. And now at 8000 mi. and a full synthetic fluid, the noise is only occasional and barely noticeable.

dannystang
04-19-05, 10:06 PM
I think your car was intimidated so it wouldn't break on you.

That spelling looks wrong...hmm

Dave's V
04-19-05, 11:14 PM
Umm, where exactly are the cadillac instructions online?

I'm going to video-tape my new rear end for the first 1000 miles.

Document ID# 1537411
2004 Cadillac CTS
03-05 Cadillac CTS , CTS-V and SRX Howl Whine
Noise from Rear Axle - kw accelerate decelerate
#PIP3051 - (Jul 8, 2004)
03-05 Cadillac CTS, CTS-V and SRX Howl Whine Noise from Rear Axle
.
The following diagnosis might be helpful if the vehicle exhibits the described symptoms in the PI.
Condition/Concern:
Howl or whine noise from the rear axle on accel and/or decel. Most noticeable at speeds between 35-50
mph.
Recommendation/Instructions:
Compare the noise to another identically equipped vehicle with similar mileage and make any necessary
repairs. Axle break in procedures must be strictly adhered to during initial break-in as outlined in the
Owners Manual. This also applies to any replacement axles that would be installed in a customer's
vehicle. For 500 miles, it is suggested that rapid acceleration be avoided, as well as to avoid driving at
the same speed for more than five or ten minutes at a time. The vehicle should also not be used for
towing during the break-in process.
.
Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is
resolved without completing every step, the remaining steps do not need to be performed. If these steps
do not resolve the condition, please contact GM TAC for further diagnostic assistance.
Models:
(03-05 Cadillac CTS) and (04-05 Cadillac CTS-V) and (04-05 Cadillac SRX)

Retrieved from Cadillacfaq in the TSB/Recall info. Towing is for the SRX of course.

dannystang
04-20-05, 12:13 AM
Thanks.