| Author | Message | ||
     James Feller Frequent User Username: james_feller Post Number: 51 Registered: 5-2008 |
Hi All, thoughts and opinions on how regularily the diff oil... opps excuse me.. final drive... should be flushed/renewed.... I had it done not quite 2 years ago.... Cheers J | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1071 Registered: 4-2003 |
James/ After the article some months back by Norman Geeson on the accumulation of deposits in Mk VI and later diffs I have been changing diff oil when I change the engine oil in the hope that the muck will be flushed out. (It's only a couple of bottles and with these new beaut filler nozzles you can plug them in jamb the bottle behind the spare wheel and go mow the laws. | ||
| Mark Aldridge Yet to post message Username: mark_aldridge Post Number: 1 Registered: 10-2008 |
Bill ,I was a bit surprised by the photos in Norman Geesons articleand a bright light in my S1 diff highlights brown muck traces despite annual oil changes ;at least during my ownership.Prior to this the car has a largely main dealer/good history.I also change diff oil in my Shadow and Bentley8 annually.Is there any merit in using an engine oil flush additive prior to change,or a flushing oil? Mark | ||
| James Feller Frequent User Username: james_feller Post Number: 52 Registered: 5-2008 |
Bill, Lindt indeed and of course... LOL! I will be in Switzerland next month, perhapes I will pick some up for the 'old girl' to satisfy 'her' chocolate cravings of course! ta though, I take it on board and when the engine oil is next due I will get the guys to do the diff as well. As a precaution now it will be done in line with engine oil changes. ta guys J | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1073 Registered: 4-2003 |
Mark/ I would like to flush diffs and actually suggested that to Norman Geeson but he was agin it. He saw pockets in the construction that would retain the flushing material and cause possible problems with the lubrication afterwards. I have never had an SY or SZ diff to pieces but I have pulled the pinion and bearings out of a Cloud III and was appalled at the crap in the thing - it was like the soured deposit left in an old milk bottle cream like very tenacious and not easy to dislodge. It does worry me though because if you read Norman's article on diffs on the KDA site of Ashley James he cites a Mk VI diff that had such serious build ups of muck that it forced the crown wheel out of adjustment! Perhaps others could comment??? | ||
| David Bailie New User Username: davidb Post Number: 7 Registered: 11-2005 |
Probably like many reading this thread I have resolved to change the oil in the diffs. of my cars at the next service. Could some knowledgeable person please list the appropriate, currently available in Australia oils for club cars? Thanks. | ||
| Mark Aldridge New User Username: mark_aldridge Post Number: 2 Registered: 10-2008 |
Bill,thanks I will change the diff oil at engine change intervals,2500 miles or 6months. David in the UK I use 80W90 gear oil,Dexron3 auto box,and 20W/50 SF rated mineral engine oil.If the engines were rebuilt, I may try a 5/60 Synthetic.My son has tried a semi synthetic in a non rebuilt Morris Minor,and it has cleaned the engine a treat.Unfortunately oil consumption has risen and the car now smokes but it runs quietly and well and oil pressure is excellent. Mark | ||
| Laurie Fox Frequent User Username: laurie_fox Post Number: 52 Registered: 6-2004 |
Bill You asked for comments about sludge in diffs. I wrote up some notes about this on my MK VI in 2006 and reproduce them here. I had always assumed that this was a problem connected with incompatible rear axle lubricants in the 1950's and am a bit surprised that later cars seem to be similarly affected. Regards Laurie "Posted: Tue May 23, 2006 12:29 am I have just been reading Norman Geeson's article about rear axles on the KDA152 website which I recommend to all concerned - the pictures are excellent and the technical content too. This all leaves me in a bit of a quandary - on the one hand the cost of a rear axle rebuild is substantial, so don't have it done unless it is really necessary and on the other hand what Norman says about what can happen is quite true. So what should the owner of a MK VI do? I suppose that the answer is to check for play in the parts as Norman recommends, change the oil frequently, see what it looks like when drained out and decide accordingly. For what it is worth here are some details of my experience, rear axle wise, on B420EY. Purchased in 1959 (I am the third owner) with 97000 on the clock with slight noise in the rear axle which Sanderson and Holmes, the main Rolls agents in Derby, could hear but I could not. A year later after doing 11000 miles I had some spare time and I removed the rear axle pinion bearing, which is quite easy to do, largely out of curiosity as I was very new to the MK VI then. All seemed OK though there was some slight play in the main pinion bearing (the old three bearing type) and I put it all back after cleaning out as much sludge as possible - especially the oilways to the main pinion bearing. The pinion nose bearing seemed quite OK. Six months later, after another 6000 miles, I could just hear the rear axle singing slightly at about 35 mph so I changed the pinion bearing so as to be on the safe side and cleaned out the sludge again although not a lot had accumulated since it was last done. After another 7 years and 90000 more miles the rear axle noise was beginning to be quite noticeable and so I stripped it all out and rebuilt it. The trouble was that the sludge in the main casing, which I could not get at when changing the pinion bearing had built up to the extent that the taper bearings locating the crown wheel were not getting enough oil and the crown wheel had moved laterally (it is spring loaded) about 0.020". I measured the crown wheel and the pinion for wear and found virtually none. The main pinion bearing was OK but I changed the pinion nose bearing and the taper roller bearings supporting the crown wheel. The whole lot was then reassembled to the original setting of the crown wheel relative to the pinion as stamped on the parts concerned. The casing etc. was thoroughly cleaned of sludge, most of which was probably due to the use of different makes of rear axle lubricant during the early days of the life of the car when the EP additives were incompatible. The car then did another 100000 miles (another 20 years) before we had the engine change and at that stage I had the pinion bearing changed just to be on the safe side although the axle was still quiet. After that the car has done just over another 100000 miles in 20 more years and the rear axle is still quiet. During that time the rear axle was drained and refilled on only three occasions (maybe I should have done it more frequently) but each time about 1 1/4 pints came out with very little sign of untoward debris and 1 3/4 pints went in so there was always a fair amount of oil there. The conclusion I have come to is that the early rear axle lubricants, because of their funny additives, did cause trouble but once they have been cleaned out there are no more problems provided you change the oil from time to time. So do you know whether your rear axle has ever been rebuilt or not. If it has then you are unlikely to have more trouble but if it has not, or you don't know, you may be vulnerable. Apart from the crown wheel and pinion there is the matter of rear wheel bearings. I have had a nearside rear wheel bearing fail. It was very difficult to diagnose because the failure was probably due to a broken cage holding the balls. Jacking the car up and turning the wheel did not disclose any trouble and the in and out play was normal. Then there was a slight screech sometimes when starting up which disappeared after driving about 50 yards. There was no more screech unless the car was reversed and then there was a screech for a short while, still difficult to locate from the driving seat. Eventually the screech did not do away after a short distance and I could identify where the screech was coming from so I got it home on a transporter. The bearing had locked and the inner race was screeching as it was staying still while the axle shaft was turning. The bearing could not be pressed out from the half shaft and so the half shaft was scrap but a second-hand (preused!) one went in OK with serviceable splines and little wear in the oil seal area. What was the actual condition of the bearing in the replacement half shaft was, of course, unknown except that it had probably been in the housing since initial assembly. But it has been there for about 80000 miles since I put it in in 1989 and the cost (1989) was 200. I know of only one other MK VI which had a rear bearing failure, also without secondary damage. So I am inclined to think that although the risk is there it is not all that high. Whether the cost of having admittedly better bearings fitted is worth while as an insurance policy is for the individual owner to decide. Regards Laurie" |
