Hi chaps
Long time, no posts as the Jag has been 'OK' thus far.

Today it has been torrential rain and major flooding in the South West. I had to drive through one flood that was long and deep. Other cars were going through it, but my Jag is lower than theirs.

It pushed its way along but soon after I noticed a very distinct pulsing grinding from the rear n/s (UK). Since owning the car since 2013, it has sometimes made this noise faintly and just briefly during warm up. There is also a slight surging of the rpm.I took it to a gearbox specialist who said it was fine, but if it got worse, to come back as it may be early TC issues.

I drove back home ( 30 miles), it kept making this noise at the 1500 rpm mark with light throttle. Below this or once accelerating, it goes away. The surging rpm is more noticeable.
In addition, going uphill introduces a judder around the same rpm.

Threads suggest anything from TC, contaminated ATF, wet coils....etc.

If a coil was playing up, due the flooding, would it exacerbate any gearbox issues? Is it coincidence that it has only occured since driving in the floods?

Any input is valued, before I take it to a garage to get my pants pulled down.

 

OK, manycars, dealing with last first . . . change garage . . . far too kinky unless your Jaguar enjoys seeing you at your finest in public!

More relevant and seriously, it sounds like driving through the floodwaters has worsened an already existing condition . . . and no coincidence at all. To your list or probables, I would add the more obvious, and easily checked once on the hoist . . . a grease seal (either rear wheel or diff) that is so worn it has perhaps let most of the good gooey stuff out . . . and has now proven useless in stopping the nasty, brown, watery stuff entering to spoil your innards. Graunchy rumblings, if bearings, will tend to be RPM related.

I know from past posts, you are not afraid of the DIY spanner twirling, so I would minimize your expense by starting at the wheel bearings . . . you may get to yell "bingo" first up.

Best wishes,

Ken

 

Sorry for double post . . . but I really should have added this explanation by way of warning to others before entering floodwaters.

Jaguars are low slung . . . I recall vividly what a 2ton Daimler V12 VDP feels like when it starts swirling crabwise back and forth over the crown of the road with family all packed in for our all night drive of 1000Km to home.

Wheel bearings, diff bearings, indeed all HOT areas along the powertrain that are protected by grease or oil seals, if suddenly subjected to the rapid cooling of being totally immersed in cold water . . . will produce a suction effect that would make your eyes water (pun intended). Result? Water is literally sucked inside to slosh around, contaminate and dilute the lubricant, which will then find it even easier to escape through the failing seal. Rusted, non-lubricated, bearings run hotter still. Repeat process leads to quicker total failure.

Not always possible, but wait for a few hours until the running gear is cool and then, only then, go snorkelling in your Jaguar!

Cheers,

Ken

 

Thanks Ken, just to mention that I never would have taken the car through the water if I could have turned around, but traffic behind me and the width of the road ( country lane) meant I had to. I have driven in floods in my daily work ride, a Skoda Felicia, without calamity and often wondered how the Jag would have coped in the same situation...now I know.

I would like it to be bearings, but even if so, that may only be part of it. The chugging uphill indicates another issue. Coil(s)?

The faint, clonking grind that I have heard before SEEMED to be from the rear n/s and usually occured during warm up AND if I was turning right on a small incline, so the weight would be on that side. Could indicate an issue on that side only, so you may be right. Now it is most definately from the rear and is enough to physically slow the car briefly, as if I'm lightly tapping the brakes on and off.

(Spanner twirling...hmmm, certainly not afraid of it but always seems to be in our cold, wet winter. Only the other week, I spent 4 hrs changing a front wheel bearing which is a fairly simple job....IF the old assembly is not seized to the suspension. Why would a car manufacturer design an alloy/steel combination?)

I'l have a look at the car today if I can and let you know what I see.

 

Remember that your transmission and rear differential are sealed. I would be checking your hubs first unless this problem existed before the water issue.

 

Wiill do. The diff has always faintly whined, but this is a loud graunching noise which seems to come from one side, so will check the easiest parts first. It has occured every now an again since I bought the car, but this is really noticeable and easily replicable, so whatever it was has got worse.

I havent driven the car today yet to see if the chugging is still there.

 

I visited two garages today, one is a Jag indy that I have used before and the other is a gearbox specialist that specialises in ZF/Jag boxes.

I came away with no real answer except that it's going to cost lots of money.

-The indy drove it, put it on a ramp and told me that 'it was the gearbox'. They offered to fit a second hand one, around £1200.

-The gearbox specialist drove it, wanted me to leave it overnight so they could do more tests but it would be £2000 for a recon of my own gearbox. They dropped me like a hot potato when I said I wouldn't be interested in paying that much.

Both agreed that it COULD be the convertor, but the ZF chap wasn't 'totally convinced'.

I was expecting a much more definitive answer from specialists.

As there are no fault lights showing, neither of them did any sort of code checking or diagnostics as they both said it was most likely mechanical and wouldn't generate a code.

So.....?

 

Hi [manycars] . . . what progress?
Past week, I have been away, so was unable to keep track of your issue. Have you jacked and checked each rear wheel for bearing wear or failure as discussed. This is a simple DIY, which follows on to removing wheel and inspecting suspension components, half shafts, universals etc.

Safety first, and doubly smart is to jack, then rest full weight on body stand . . . finally, handbrake OFF and g/box in NEUTRAL. OK? Start with a fairly beefy rocking of wheel and tyre in both 6 & 12 o'clock then 3 & 9 o'clock planes. Then, rotate wheel in forward direction, slow at first then gently increasing speed. Repeat in reverse direction. In all these tests, some small degree of play is acceptable, but any grinding, jumping, or just plain graunchy . . . can all spell a failed wheel bearing or half shaft universal joint.

No? Then, with car still on body stand and assistant on brake pedal, remove the jacked wheel. Now, using a short pry-bar . . . yes, that's right . . . apply sufficient pressure against all components mounted on rubber bushes, to test their integrity. This does NOT mean crow-barring components to destruction . . . we are aiming to replicate the sort of deflections that these components do hundreds or thousands of times each day. Your symptoms may indeed reflect failure of link bushes.

Until proven otherwise, I would treat the doomsday prophesies of your experts as "last resort". . . one or the other may indeed be correct, but the strategy I am recommending starts with you spending no more than an hour of your time per side, and using basic tools you probably have.

Oh . . . and did I mention . . . it won't cost you 2 grand to do so!
My apologies to the Great British Pound, but my k/b doesn't know you!!!

Do let us know how you are faring.
Best wishes,

Ken

 

I tend to view 2K as "we don't want to do it unless we profit greatly". Or, "go elsewhere".

 

Sad . . . regretful . . . and surprisingly universal. Whether UK, USA, Canada or Australia, this is a common experience . . . and I don't just mean the 2K price . . . I mean the look of derision and blatant "don't care" when quoted work / price is beyond the customer's reach.

Having just bought 2x 1979 Jaguars . . . an impeccable SIII XJ6 for my menagerie . . . and then an absolute "bucket of bolts" XJ-S as a project car (potentially Historic Racing track car; Hahaha!). I was motivated to purchase a range of Maintenance and Restoration books - all from respected authors like Nigel Thorley, Dave Pollard and the like. Most had some brief history of the rise of Jaguar under Lyons; stylists like Sayer, PininFarina; engineers like Hassan. There were the glory years - winning on track, and bulging order books!

But all pointed to Jaguar's three HUGE weaknesses -

• after Lyons' departure, the BLMC fiasco of poor management, even poorer financial commitment, and increasingly absent quality control, meant that for much of the 70's until Egan arrived in early 80's, Jaguar had hopelessly antiquated paint lines that constantly failed . . . leading to haphazard paint thickness and even worse . . . a decade of paint quality and underbody rust prevention that lagged even the most basic of the rapidly emerging Asian car manufacturers;

• for some as yet unexplained reason, Jaguar either failed to understand, or could not control, their network of dealers and the training of technicians . . . how else can one explain the litany of failed or incorrect diagnoses, wastage of indiscriminate parts replacement, and sometimes outrageous maintenance costs. No, not all are "duds" . . . many are truly "great" . . . but it is appalling that Jaguar has left it up to individual owners to sort out which are "up to snuff" and which to avoid . . . and it is STILL OCCURING;

• the company has often failed to act promptly on customer and dealer feedback . . . by the 70's, any decent car should NOT leak . . . No, the golden, red, green, or black stuff so necessary to the Jag's internals, should NOT end up on garage floors . . . nor, equally seriously, the wet wintry stuff flung at us by nature should not end up inside cabin or boot, to wet carpets and rust out floors . . . . yet Jaguars, despite their marketing, did both . . . window and door seals, in the main, simply didn't work, and . . . Jaguars leaked!

May not be everyone's experience of 70's - 80's Jaguars, or the Dealers who are (frankly) not interested in them. But it was the cautionary theme in all of these books. In that light, and now IMHO, it makes [JaguarForums.com] and gurus like [JagV8], [Gus], [Grant Francis] and many, many others such incredible value.

Cheers,

Ken

 

At least the last 2 bullet points apply to many marques here, some let me say this carefully, German ones, for example. Customer service extends to SALES and that's it. Servicing is poorly done and very costly. Reliability is bad.

 

Yep; I agree.
I too, am trying to be careful . . . easy to read my post as an anti-Jaguar rant. Far from it . . . I love the marque, and have bought both used and new Jaguars for near on 50 years! Just occasionally, the frustration seeps out.

Cheers,

Ken

 

OP, I bet you have slipping clutch pack in your transmission. Moisture got in and is causing the slip. It happens during light load/low rpm situation and slightly accelerating as that's when the clutch pressure is low.

You can try to add transmission additive such as Dr.Tranny shudder fixx. If not, it would mean opening up your transmission to do refresh of TC clutch pack.

 

Hi Chaps, I've fairly well resigned myself to binning the car, but did get the rear up on stands. Started the engine and put it in D. There is a rotational grumble from the back end, same side as I can hear the noise when driving. There is a surprising amount of bobbing up and down too, like unbalanced wheels.

After a brief investigation, as it's bloody cold/wet/foggy here at the moment, it didn't show any noticeable wear. There is some slop in the diff when you rotate one side against the other, but whether its more than to be expected I'm not sure. The half shafts do not seem worn or slack at the hub end.

I'm 99.9% sure the main issue is gearbox related, as it only does it when the engine is at operational temperature, when the box fluid would be thinner.

I've visited another auto specialist near me, who also condemned the gearbox. He suggested that it was brass bush/bearing wear in the output shaft, he's seeen it before. He mentioned 'lock up' and that he has experienced similar on some Mercs where the noise is transmitted to the rear. He mentioned the additive, but said that it wouldn't really help now.

I'll try another garage, one that doesn't 'specialise' in auto's and see if they suggest another, simpler diagnosis.

 

Ouch! Not good [manycars].
I guess my final suggestion would be a friendly hoist and parting of the rear prop shaft to diff - this would give final certainty to whether problem is confined to rear end (which your placing of the graunch appeared to indicate) or comes from further up powertrain. You mention "binning" car. Are there no avenues for an a/t and t/c exchange or refurb, if such is required?

Best wishes, and please do advise outcome.
Ken

 

By 'binning' the car, I mean selling it as is to the highest bidder. It will mean a loss financially, compared to what it could have fetched 2 weeks ago, but it really looks like gearbox issues.
A second hand 'box is going to be £1200 fitted ( £500 for 'box, £250 for fluids, rest for labour and VAT) and a recon of my existing 'box is £2000.
If I was planning to keep the car, I'd do it, but I've already bought another car to keep me going. The ££££s keep on floating out of my wallet at the moment!