Q45 Drive Shaft

[jamesmost]

my drive shaft flex disc is shot infinity says have to replace the entire drive shaft-- any one know where to get flex disc after market??

[Q451990]

Nope... some members have replaced the entire driveshaft with aftermarket, but with poor results. It's a very DIY-able job with four jack stands, but you'll probably be best off going with a new assembly from Joe. Another possibility is finding a low mileage take-out - but it's only going to be a year newer than yours at best.

Typically the failure is with the center carrier bearing (aka doughnut) but I guess the flex bands could go bad too...

Heath

[Q45tech]

Be sure to change the transmission tail shaft seal.

The problem is the whole shaft and the 3 parts are balanced trued/phased as a unit............changing any parts changes everything............but so does age a 9 year old unit will be funky as the phase has change due to rubber and internal changes.

[HeavyDuty]

Also, per the FSM, note the orientation of the paint stripe on the diff itself corresponds with a stripe on the end of the driveshaft.

[jamesmost]

i spoke to a guy in cali who replaces the flex disc w/ a manual tube yoke says works well my mechanics drive shaft guy says the same

[Q45tech]

"Works well" has many meanings!

Every other than factory drive shaft we have used [carbon fiber, aluminum, 1 piece solid, etc] at customer request was subsequently removed and returned to vendor. at owners cost!

There are professional drive shops who can build and balance but the days and weeks of labor to get it to match the oem can be expensive.

To get the phasing and balance to as new is a serious day long effort [even with a new oem drive shaft] as the pinion gear and rear flange have changed.

Owners won't pay for the phasing labor nor the 4 hours of drive testing.........they just get the marks matched which is good enough.

It takes 1.0 hours to get the car to the only shop I trust [for off and then on car strobe/accelerometer balancing] and they have a 2 week backlog...............usually necessary to drive and measure vibration frequency [with their $10,000 analyser] then return with the data try a fix then drive again and again and again.

I've done it twice and the bill was $800-1,000 after the normal shaft swap price.Good luck, just don't spend time reinventing the wheel.

[texasoil]

It depends on your tolerance for vibration.

The only practical way to return your car to absolutely smooth driveline is to restore it to OEM state--new engine&transmission mount, new exhaust hangers, new driveshaft, maybe new differential bushings too.

That said, a conventional yoke is not recomended as it will send speed variations up and down (down the driveshaft, up to the transmission) twice per revolution unless it has a zero angle of deflection. I don't think the 'rubber' coupling between the inner and outer rear sections of the driveshaft will last long with that constant torsional vibration--maybe it will.

The 'rubber' drive disk is carefully designed to absorb the torsional vibrations caused by its angle of deflection so as to keep the driveshaft and transmission under constant load--no speed variation of the driveshaft.

I really don't think any modification that is even close to OEM smoothness can be done for anywhere close to the new shaft from Scottsdale Infiniti.

IF you are tolerant of driveshaft vibration, or drive only at low speeds, maybe the hard yoke will work OK for you.

[Q45tech]

We see lots of wear on rear tail shaft [transmission] seals and bearings.........and the input pinion seal and bearing [differential] FROM running out of balance driveshafts.

Things sag.......that's why there are washers to set the exact center angle on the shaft.

[jamesmost]

i have a drve shaft comming tomorrow from http://www.driveshaft.com steve from there has a 97 Q45 with his shaft on it for 3 years, has a slight vibration @ 80mph onlyhe said i should run it for a couple of weeks and if i am not happy he will reimburse all of my money including shipping. i spoke to someone from the forum who had his shaft(interesting wording)had a vibration sent it back for full reimbursment, put on a factory shaft and had same vibration. i will advise next week if it was $$ well spent

[jamesmost]

new driveshaft is in (aftermarket - http://www.driveshaft.com) took the car out last night, except for hitting a huge east coast crater sized pot hole and wasting a brand new pirelli p-zero. all seemed well and good got her up to 90mph and no problems feels greatwould recomend this driveshaft

[Q45denver]

How much are they?

[jamesmost]

$385.00 plus a 60.00 core charge this includes freight both ways there is a wholesale price to shops as well

[Q45tech]

$445 vs oem price.......each to his own.

We tried a few from them [their supplier] not quite up to oem.

[jamesmost]

U DO GET TE CORE CHARGE BACK - FROM THE DEALOR THE SHAFT NO PUN INTENDED IS $700.00 OR $531.00 IF U ARE A SHOP OR UR MECHANIC IS COOL. THE JOBER PRICE FROM DRIVESHAFT.COM IS $275.00 THUS U CAN SEE THE DIFFERENCEI AM ON DAY 3 HAVE NOT EXCEEDED 90 MPH AND FEELS FINE AND DANDY, BY THE WAY I AM A VERRY SENSITIVE GUY NO PUN ONCE AGAIN JUST THOUGHT I WOULD SHARE MY EXPERIENCE

[jamesmost]

I WIL TRY TO OBTAIN HIGHER SPEEDS BY MONDAY AND WILL INFORM ALSO FULL REIMBURSMENT WAS PROMISED IF I WAS UNHAPPY AFTER A COUPLE OF WEEKS, MABY I WILL GET A CHANCE TO STROBE IT THIS WEEKENDCHAO

[Q45denver]

Will a 1995 driveshaft fit on a 1993 Q45?