Hi,

New member, first post

purchasing an L322 TD6 Vogue but the previous owner (thankfully) has been honest and stated there is an issue whereby at approx 1800rpm the car gives a slight shake, hot or cold but this passes as soon as you go past this part of the rev range. When you come back down again it happens again.

Also apparently has slightly rough running on reverse (he's been told that during reverse the RR uses low revs so that's why but obviously there is an issue there)

Worried it could be symptomatic of a much larger issue and/or big repair bills.

Is there any advice somebody can give to enable me to make a better diagnosis (as best as possible in this situation)?

Thanks all!

Other's much wiser on L322's on here may correct me but it sounds like the notorious TD6 transmission packing in. Most describe this as more like driving over a cattle grid though.

martynv8 said:

Other's much wiser on L322's on here may correct me but it sounds like the notorious TD6 transmission packing in. Most describe this as more like driving over a cattle grid though.

Click to expand...

Would that cause shaking at a particular part of the rev range?

Temped to start looking at the V8 petrol's also as they are cheaper to buy - believe they don't suffer as much as the td6 ?

thanks

Apparently so.
Like i said, other more knowledgeable members should be able to help.
The V8's do suffer with transmissions but not as dramatically & can be caught in time. SaintV8 on here could offer much more advice about this.

martynv8 said:

Apparently so.
Like i said, other more knowledgeable members should be able to help.
The V8's do suffer with transmissions but not as dramatically & can be caught in time. SaintV8 on here could offer much more advice about this.

Click to expand...

Cheers mate

jaipal2004 said:

Hi,

New member, first post

purchasing an L322 TD6 Vogue but the previous owner (thankfully) has been honest and stated there is an issue whereby at approx 1800rpm the car gives a slight shake, hot or cold but this passes as soon as you go past this part of the rev range. When you come back down again it happens again.

Also apparently has slightly rough running on reverse (he's been told that during reverse the RR uses low revs so that's why but obviously there is an issue there)

Worried it could be symptomatic of a much larger issue and/or big repair bills.

Is there any advice somebody can give to enable me to make a better diagnosis (as best as possible in this situation)?

Thanks all!

Click to expand...

Sounds like torque convertor break up, if you catch it early you can save the gearbox.
The GM box on the Td6 is pretty poor, the valve block is made of soft cheese.
The ZF box on the V8 also suffers failures, plenty of info and pictures if you do a search.

:welcome2:

First - ignore the ball-cocks reason for juddery reverse...the Range Rover doesn't all of a sudden go into a low rev mode for reverse....it does have a lower gear ratio in reverse than 1st, but this is similar for the majority of cars...Reverse is a lower gear than 1st!

That being said, due to this slightly (and I mean slightly) lower gearing in reverse, any rough running could show up worse in reverse, but only margainly and so as would not really be noticeably different to first!

The TD6 is a common rail diesel, this means all the injectors are connected to the same high pressure fuel pipe and as such are all fed the same high pressure fuel, so it is unlikely to be an injection issue as it only happens at a certain rev range. If it was an injection issue, I would expect it to happen constantly pretty much.

The GM5 box fitted to the TD6 models was unfortunately poorly made, or more specifically, the valve block was poor quality material....

The Valve Block contains shuttle valves to direct hydraulic pressure to engage or disengage the drive clutches....one such valve operates the Torque Converter Lock Up Clutch and another modulates hydraulic pressure from the pump....

The operation of the GM5 Lock up clutch has different 'modes': Slip (Stand still), Limit slip to 3% (Driving) and Locked up (Cruising)....

As can be imagined, in order to limit the TQ slip to 3%, the lock up clutch is being applied and released many times (its modulating) to control the slip, so this little valve is moving about a lot....this constant movement in a valve bore made of cheese wears the bore considerably to the point that hydraulic pressure is lost and the TQ starts to slip more, this wears out the friction material on the Lock Up Clutch plates and all this material gets deposited into the gearbox oil turning it gritty and like a cutting paste...

This now dirty oil circulates the system and into the valve block, where the valves are moving about....wearing out the bores even more so as they are now sitting in this cutting paste oil...dumping more debris and crap in the box and oil....a viscous cycle ensues until the box goes pop....

Similar process with pump modulating valve...this is constantly moving wearing out the bore it sits in causing hydraulic pressure issues, which in turn means the friction plates in the drive clutch lose pressure and slip dumping much un-needed debris into the box....the GM5 box is destined for the bin!

Most often you won't get much warning of the GM5 box going south, but there have been reports of juddering or sudden lose of drive and reverse...then all of sudden you get drive again....this is due to the dirty oil in the valve bores...

The Petrol V8's ZF box is also not as good as it should be, but is more robust than the TD6 GM5 box....

The ZF box weak point is a bearing between B+C Clutches and an O Ring in the A+B clutch pack...the bearing fails, allowing the A+B clutches to move axially on the shaft, this wears the O Ring underneath that seals A Clutch from B Clutch....the O Ring fails, and hydraulic pressure is lost in A Clutch....as A Clutch is used in all gears apart from 5th and (I think) reverse, you all of a sudden can't get drive until you rev the nuts out of it and it bangs into 5th gear and all the bells and whistle go off telling you of a Transmission Fault!

The ZF Box tries to limit this hydraulic pressure loss by modulating the TQ to limit the slip on the A Clutch...this prematurely wears out the Lock Up Clutch causing a judder usually felt between 30-45mph on a slight gradient or under light acceleration....the rev needle can be seen to bounce around too, about 100-200rpm in sympathy to the juddering vibration, this juddering is akin to driving over a cattle grid....

The ZF box will give warning via this vibration before it gives up the ghost, and some have reported driving over 20k miles before doing something about it...I wouldn't advocate leaving it that long....whereas the GM5 box on the TD6 can just let go all of a sudden with little to no warning!

What didn't help is LR saying the gearboxes were filled for life and maintenance free....this has since been revised with oil changes and filter changes every 50k miles...I would do it every two years or 24k miles mind....

Dropping the oil out of the box and looking at the filter and magnets in the sump can give a good indication of box wear.....

Remember the Golden Rule to Range Rover Purchase: Never Ever buy a Range Rover with a fault unless you are prepared for and appreciate the potential cost, time and frustration involved in repairing it...they can empty a healthy bank balance rapidly!

Nice reply Saint 9