| Author | Message | ||
     Jeffrey McCarthy Grand Master Username: jefmac2003 Post Number: 365 Registered: 5-2007 |
SRH20280 developed a strange intermittent vibration through the steering wheel on the drive home from Sydney. Usually this occurred in the lower gear ranges so I'm assuming the gearbox is in need of a service. The transmission was completely rebuilt about 14 months ago and the car has been largely off the road since. I'll check all the electricals prior to the servicing in case it's just the switch (also recently renewed). Contrary to my request the rebuilder filled the trans up with Dexron III instead of the synthetic - "because it doesn't need it". Three questions: 1- is there anything else I should check; e.g. in the steering before I take it down for servicing ? 2- is it possible to drain the Dexron III completely and replace it with modern synthetic without paying through the nose for an almost complete rebuild? 3 - Search as I may I can't find the name of the synthetic fluid that Richard Treacy recommended - is it Transmax something? | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 937 Registered: 6-2006 |
Dexron III should not be the problem, especially after such a short period. It's hard to change ALL the oil but before deciding to go that route, consider that some Shadows are still driving around with 30 year old dexron II in! So III will be OK for a while!  Did you have the initial service / fluid change done after the rebuild? I would look at flat spots on the tyres if the car has been standing still on them. Balance. Pressures. Low level misfire? Old fuel / condensation in tank. Oil and grease in half shafts. Prop bolts? Is it under load? Low speeds? Coasting? | ||
| Jeffrey McCarthy Grand Master Username: jefmac2003 Post Number: 366 Registered: 5-2007 |
Unfortunately Paul the accident requiring the 9 months off-road happened a couple of weeks after the transmission rebuild so no service has yet been done. All the fluid levels were checked and the coolant renewed in Moss Vale before I got the car back 6 months ago after the bodywork and a complete greasing (including the diff) was done then. The oil was changed a month and a half ago. The problem didn't manifest itself until after I'd driven 600klms or so - would tyre flat spots manifest before that? Generally seemed to happen more often when accelerating from lower speeds up to freeway speed. I'll take it for a test drive tomorrow and take careful note. At some point I'd really like to replace the Dexron in any case as I'm not really confident about continually topping up the trans fluid with the danger of over/under filling. | ||
| David Michael Leedy Experienced User Username: dleedy Post Number: 12 Registered: 11-2011 |
Hi. I had a discussion with the rolls royce parts manager in Nj about this very subject about steering vibration and he stated that it's almost certainly the tires. Many rr owners do not Drive their cars often and due to the heavy weight of these cars the tires warp and the fix is almost always tire replacement. This happens so often in fact that he diagnoses this on a weekly basis. | ||
| David Gore Moderator Username: david_gore Post Number: 1195 Registered: 4-2003 |
I would expect any flat spots on the tyres would have been "worked out" after 600Km of driving - even more so if the driving was during one of our recent hot days. I would be looking at the universal joint retaining bolts and the engine/transmission mounts. The fact that it is occurring mainly under acceleration suggests a drive train rather than a suspension problem. Like Paul says, Dexron 111 is suitable for your T400 transmission. I would not consider a synthetic oil unless the torque convertor could be drained, flushed and refilled during the changeover. | ||
| Jeffrey McCarthy Grand Master Username: jefmac2003 Post Number: 367 Registered: 5-2007 |
David -this is the universal joint of which you speak?  I'll pore through the manual and see what access is like to the retaining bolts. The engine mounts are only 3 years old and there have been no oil leaks on them since but I'll get the mechanic to have a look while it's on the lift for the transmission service. | ||
| David Gore Moderator Username: david_gore Post Number: 1196 Registered: 4-2003 |
Yes - but where is the grease nipple? I absolutely abhor sealed-for-life universal joints due to their propensity to fail at the most inconvenient time often without warning. You should be able to source greasable universal joints from industrial suppliers - I used to get them direct from Hardy-Spicer at Moorebank NSW. A worn cruciform/bearing cup and/or loose cups in the yokes are possible causes as well as loose flange attachment bolts between the gearbox/driveshaft/differential. The engine transmission mounts would most likely be a case of loose fasteners or a sheared mounting block. | ||
| Jeffrey McCarthy Grand Master Username: jefmac2003 Post Number: 373 Registered: 5-2007 |
As far as I know David I still have the original on my car - the photo is of a replacement offered by one of the UK suppliers; I'll have a chat about this next time I'm down Bayswater way. The steering hasn't even been looked at in about 2 years. Did the original have a grease nipple? | ||
| gordon le feuvre New User Username: triumph Post Number: 4 Registered: 7-2012 |
If standing height is low on rear, as car dips under acceleration/load angle of driveshafts increase? If car has inner detroit joins ( big rubber boots on them) make sure these are topped up with axle oil.If the boot has split and and let the oil out, this can cause seizure of the sliding aspect of the joint. The amount of oil is in tec ,manual. Easy way to check if car is low at rear, run engine for 4 mins, look at top part of wheel arch. Tyre treadshould be about hidden by 1/2 inch at most | ||
| David Gore Moderator Username: david_gore Post Number: 1198 Registered: 4-2003 |
Hi Geoff, not certain but would be very surprised if the originals were sealed-for-life. | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 941 Registered: 6-2006 |
Tyres that have been sitting for a while will often improve with use and rebalancing. You will probably find that from dead cold you will always get a slight wobble. UJ's They did, should have, and NEED nipples. Often they are loose in the bag so may not be in the photo. (You need them out of the UJ to fit them on the car.) They will last forever (practically) if greased up annually. Later cars have the grease nipples deleted on their prop shaft UJ's . Most are blanked with a grub screw. Fit a nipple, grease them and , Once again, they will last. When an item is called sealed for life . . .don't be fooled into thinking that it means for the cars life - or your life - or any useful length of time. It just means it is sealed until it wears out because of lack of lubricant! Same goes for steering ball joints, half shafts, etc. Lubricate them all annually (or more often if higher mileages are done) and they will last. Some pics of what you are trying to avoid at: http://www.facebook.com/pages/EverythingRollsRoyce/480142005358985 |
