[ZAMP]

CVT not the culprit

Zamp here with an update from CVT went south. Yesterday 5-7-4 My Mo AWD SL should have been finished .So I went down there to see for myself the progress.( I’m trying to separate fact from fiction because I think that there is a major learning curve going on with my Mo on how to repair) but service manager stated two things. The replacement cvt did not arrive till that day and it came without the rear differential attached (He should have only ordered that and not a CVT.) They had to drop the engine in order to remove the CVT.
And as it turns out, The CVT is just fine. It is the Rear Differential that failed (Blown Ring Gear).What bothers me is that the service manager stated that there were metal chips seen in the draining of the cvt fluid. I think to myself that cant be because the Rear Differential is a separate but attached component with different fluid (80wt.Gear Lube) I don’t particularly care for the service manager because he is the arrogant type who talks to you with his know it all attitude, says one thing then turns around and says another as if you know nothing. It also bothered me standing there looking at the engine-cvt-lower cross-member w/steering rack hanging from chain on cherry picker. As I looked at it I thought couldn’t they have just removed the Rear Differential with out having to pull engine and all? Sure it makes for easy access to everything when motor is out but can they put everything back together nicely like factory with no extra screws or bolts or clamps lying around, I sure hope so. So on a good note it is comforting to know that the CVT is not the problem itself but how to transfer power to the rear.

P.S. All FWD MO owners need not be concerned.

 

[Dookie]

Isnt the rear diff on the rear axle?

 

[ZAMP]

Dookie

This is the Front-Rear Differential (Or Transfer Case) that failed (Blown Ring Gear). Basically you have two of them in awd models. Front and Back. The Back Rear Differential has two spider gears within the ring gear to control limited slip at rear wheels.
Picture also shows holding a Gear Tooth.

 

[ZAMP]

And more...Have many more views if needed.

 

[ZAMP]

Side view

 

[Eric L.]

I like the view of the tiny oil filter on the large engine/transaxle assembly.

So what exactly failed? The front differential or the rear differential? I am confused.

Also I do not know if this helps, but the front differential and rear differential each have their own gear oil assemblies separate from the CVT. The metal chips in the CVT fluid could not have possibly come from the differential. I would try to get some clear answers from that service advisor of yours.

 

[ekaxel]

The Back Rear Differential has two spider gears within the ring gear to control limited slip at rear wheels.

BTW: Rear differential on a MO does NOT control limited slip!

 

[senza]

The spider gears in the differential actually allow "slippage"; they allow each wheel to turn at different speeds eg when going around a corner. Zamp... I assume the engine/cvt was "dropped" from the vehicle and is just being moved around on the cherry picker?

 

[ZAMP]

Senza
The spider gears in the differential actually allow "slippage"; they allow each wheel to turn at different speeds eg when going around a corner. Zamp... I assume the engine/cvt was "dropped" from the vehicle and is just being moved around on the cherry picker?

Yes your right about both slippage & the cherry picker. You are detailing my statements better then I.

Here is another view of the transfercase that failed.

 

[Tyler_Canada]

The rear differential housing also contains an electronic clutch which determines the amount of torque sent to the back wheels.

 

[ZAMP]

A more detailed explanation of LIMITED SLIP DIFFERENTIALS
The conventional differential delivers the same amount of torque to each rear wheel when both wheels have equal traction. When one wheel has less traction than the other, for example, when one wheel slips on ice, the other wheel cannot deliver torque. All turning effort goes to the slipping wheel. To provide good even traction even though one wheel is slipping, a limited slip differential is used in many vehicles. It is very similar to the standard unit but has some means of preventing wheel spin and loss of traction. The standard differential delivers maximum torque to the wheel with minimum traction. The limited slip differential delivers maximum torque to the wheel with maximum traction. Other names for a limited slip
differential are posi-traction, sure-grip, equal-lock, and no-spin.

As a simple test to determine if the Murano has limited slip or not, I rotated right rear wheel clockwise by hand while car was up on lift in park and noticed left rear wheel turning counter-clockwise with minimal effort. It is my belief that the Murano does not have LIMITED SLIP but a conventional differential. Because if it had LIMITED SLIP, I should have felt significant resistance when rotating either rear wheel.

 

[jaak]

AWD LOCK SWITCH
AUTO mode

Electronic control allows optimal distribution of torque to front/rear wheels to match road conditions.

Makes possible stable driving, with no wheel spin, on snowy roads or other slippery surfaces.

On roads which do not require AWD, it contributes to improved fuel economy by driving in conditions close
to front-wheel drive.

Sensors determine the vehicle's turning condition, and in response tight cornering/braking are controlled
by distributing optimum torque to rear wheels.
LOCK mode

Front/rear wheel torque distribution is fixed, ensuring stable driving when climbing slopes.

Vehicle will switch automatically to AUTO mode if vehicle speed increases. If vehicle speed then
decreases, the vehicle automatically returns to direct 4-wheel driving conditions.

LOCK mode will change to AUTO mode automatically, when the vehicle speed exceeds approx. 30 km/h
(19 MPH). The AWD LOCK indicator light keeps illuminating.
NOTE:

When driving in AUTO mode or LOCK mode, if there is a large difference between front and rear wheel
speed which continues for a long time, oil temperature of drive system parts becomes too high and AWD
warning lamp flashes rapidly. (When AWD warning lamp flashes, vehicle changes to front-wheel drive
conditions.)

If AWD warning lamp is flashing rapidly, stop vehicle and allow it to idle for some time. Flashing will stop
and AUTO mode will be restored.

When driving in AUTO mode, AWD warning lamp may flash slowly if there is a significant difference in
diameter of the tires. At this time, vehicle performance is not fully available and cautious driving is
required. (Continues until engine is turned OFF.)

If the warning lamp flashes slowly during driving but remains OFF after engine is restarted, the system is
normal. If it again flashes slowly after driving for some time, vehicle must be inspected.

When the difference of revolution speed between the front and rear wheel with AUTO mode the shift occasionally
changes to LOCK mode automatically. This is not malfunction.

If there is a significant difference in pressure or wear between tires, full vehicle performance is not available.
Tire conditions are detected, and LOCK mode may be prohibited, or else speeds at which LOCK
mode is enabled may be restricted.

 

[jaak]

.

 

[Dave N]

Sorry to see that your Murano has to have such extensive surgery. After looking at the pictures of the motor sitting out of the car I began to think: "now would be a perfect time to chrome some of those hard to reach engine parts"

I hope it's back in service soon.

Dave

 

[ZAMP]

Dave

Sorry to see that your Murano has to have such extensive surgery. After looking at the pictures of the motor sitting out of the car I began to think: "now would be a perfect time to chrome some of those hard to reach engine parts"


Gee I don’t know if have some engine parts being chromed would be a good idea for me because it might void the cars warranty. But if it doesn’t, the money might be better spent on a (Oh I Don’t Know Maybe Something like an Extended Warranty Perhaps)!!!

No offence but it’s been a long hard ride without the long and winding road with shoddy repair service.
:3: