Hi all, this will be my first post here. I did search the forums before deciding to write this and I figure it's appropriate because I haven't yet read anything that goes quite like this:

I recently had the rear differential fluid changed in my 2016 F-Type R AWD by a 'European auto shop'. I had a different mechanic test the fluid a couple months ago and they said it's very mildly dirty but because I know the rear diff is a common failure point of this car I ended up having the fluid changed anyway out of caution. After having the fluid changed, I'm noticing a very low-pitched clunk from the rear when I hit 7-10mph after driving forward from a stop. I hear and feel no noise when changing from park to drive, to neutral, to reverse, etc, but once I start moving, after speeding up to around 7-10mph I'll hear a clunk. It will occur once and not occur again until I slow to a stop (and no clunk when slowing, as far as I can tell) and then speed up again to 7-10mph. I could swear I'm hearing it particularly at the rear left. I've heard it both while turning and while driving straight. Typically I'm hearing it when I'm driving on flat ground.

There was no such noise before I had this fluid change, and it started immediately after the fluid was changed. What could someone have done to cause this when changing the fluid, if anything? Or, is there something the mechanic could have aggravated by, say, removing the rear left wheel to service the rear diff? Could it be an issue with the suspension?

Thanks for any help or advice, I appreciate it.

 

First thing, make sure they put the correct fluid in.

The E-Diff requires a particular Castrol BOT-720 fluid, it's only available to purchase from Jaguar Land Rover.

If they put in the wrong fluid, it'll cause these sort of issues.

Comes in one litre bottles, LR019727 from Land Rover, C2D3650 from Jaguar.

 

Thanks for the reply. I should have mentioned: they used Motul 75W-90 Synthetic Gear Oil, which I've read elsewhere on the forum is a reasonable replacement for the fluid JLR uses - is that right in your view? As for the exact amount used, I have no way of knowing; I asked if I could get a chance to speak with the technician to ask some questions when I took the car back, but they basically told me they don't normally do that (lol). The work order says "Qty: 2"...

A couple of other things:

-The trunk is completely empty when this noise is occurring.
-The car has 38,000 miles on it

Also, I'm noticing after another drive that to make the clunking noise occur, I can speed up to about 8 miles an hour, very lightly press the throttle for a second until I hit 10mph, then almost immediately after I let go of the throttle I hear the clunk. If I do this speeding up and slowing down routine repeatedly, the noise will occur once each time I let go of the throttle at 10mph.

 

I don't have an opinion on the Motul product.

What I can tell you, is that I've seen & driven an XFR that had the wrong fluid put in the E-Diff, and it clunked & chattered.

Do you really think it's a coincidence that this noise started after putting in a fluid that is not the factory spec?

 

I guess that if to the contrary I assume that the fluid they used is incompatible with the differential in this car, the first thing I ought to do is see if I can get them to redo the job with BOT-720. I just figure that that wouldn't be exhaustive of things that could be wrong, but we'll see I guess, I can update the thread when I call the auto shop that did the work next morning. Thanks.

 

Hi,
I have this one in my Diff, and it runs perfect!
https://www.ravenol.de/de/produkt/ge...-differentials

Is your Motul also for BOT 720 approved? It will be sign on it.

My Ravenol recommendation is BOT 720! Please check this for your Motul.
If there are any problems I would swap to the Ravenol as soon as possible, or BOT 720 original if you are not sure.

 

So I took the car back and they were extremely apologetic about the issue (and not in a facetious, corporate way, from what I could tell), I spoke with the mechanic and he didn't even ask to ride with me to replicate the issue, I had an easy time letting them know they should have used the JLR-recommended fluid. I spoke with the mechanic about making an effort to flush as much residual fluid as possible, hopefully the issue disappears when they're finished with the fluid change.

Now I'm wondering, what are the chances that I've done any lasting damage by driving the car with the wrong differential fluid in it? I think I drove about 30-40 miles (less than 1 mile of it spirited, really) with the wrong fluid in the car. Anything I should look out for?

EDIT: The fluid change is done and issue is still present. If we suppose the noise has nothing to do with the fluid, what could be causing this? Is there a TSB floating around that addresses something like this?

 

I am having this exact issue in my '16 R.

It's been slowly getting more noticeable. I'm at 28k miles, bought the car this spring with 24k.

I've had nothing but arguments on other issues with my dealership, and I am not confident that if I take it back for this issue that they will make a decent attempt to diagnose.

Please keep us updated.

 

I bought my car this past June as a CPO, the CPO warranty ends October 30th but I'm worried they'll do what you're describing because the issue is pretty subtle compared to other things I read about. My appointment with the dealer is on the 18th so I'll definitely chime back in with what they tell me around then. I'm doing my best to investigate things myself before the appointment so that I can give them as much to go off of as I can.

One more thing I noticed: If I put the car in manual mode and force the car to stay in 2nd, the issue still occurs (so maybe that lends credence to the idea that it's not a transmission problem, other than the car having no issues shifting at all). Right now I'm really betting on a worn bushing or mount, maybe a rear differential bushing or mount, or a suspension component bushing, though I could swear I'm hearing the clunk dead center in the rear. Unfortunately I don't have room or the tools to jack the car up right now, but I would love to. I've diagnosed and fixed a lot on this car on my own, but I don't have the access for this one.

 

Same situation here - bought CPO, and my warranty runs in January. I have already had the exhaust replaced under the warranty, and have had it in 3-4 additional times for a leaking whistle sound from the left rear and a hesitation/stumble on initial throttle input...but they've taken to treating me like I'm a rather ignorant child and told me that despite hearing the noise, they can't find anything wrong, and I'll just need to deal with it. Not to mention their valet driver hit a construction barrel on the highway while delivering it back to me the last time, and didn't mention it to me on delivery. I only discovered it because I later saw an orange scuff on the front lip and then checked my dash cam.

I love this car - so very much - but this JLR/JLRNA/JNA dealership has soured my experience with ownership so much that I'm considering giving up entirely. I can handle normal maintenance items myself (highly recommend QuickJack), but more involved issues like these are beyond my budget (time and money).

Oof - sorry for the rant. Anyway - I'll go out later for a drive and see if I can also replicate the clunk in 2nd in manual mode. Mine also sounds like it's dead center in the rear, doesn't seem to come from either side at all. If you had access to a lift, what in particular would you be looking for under the car to help diagnose the issue?

 

Yikes, this is the kind of thing I'm afraid of. Don't get me started on my last dealership experience, they misaligned my hood and cracked my front bumper...

If I could get under the car, I'd have a lot of patience poking around looking particularly for any excessively worn, cracked or ruptured rubber (i.e, a failing bushing), also any play in any of the suspension components or the driveshaft. I actually have very little mechanical experience but everything else I've diagnosed and fixed has come from me being patient staring at parts of the car and jiggling things around.

I feel like it's gotta be something connected to the differential, but not the differential itself, or maybe a worn universal joint... It'd be cool if another experienced member here could chime in, I'll wait patiently for that too... though this problem is pretty obscure.

 

The only time my F-Type developed a clunk from the diff area was when the electrical connector on the fuel pump worked loose and started making intermittent contact. When it was diagnosed and clipped securely back in place all was silent again. I also had some codes indicating fuel rail pressure issues.

 

Interesting... Honestly I kind of wish the car would throw a code, at least I'd have a hint then. Unfortunately it's looking more subtle than that, even. For all I know it'll throw one tomorrow, but the car's been driving perfectly.

 

Probably not going to resolve or figure this out by guessing at it. Best to have a shop put it up on a lift, replicate the conditions, and get under the car and look/listen. It could be something that was moved or removed during diff change and not put back properly.

DC

 

Thanks for the reply. Believe it or not, I asked the mechanic that did the job several times about what he had to remove to get to the fill plug, because I thought the same thing, and he said he removed nothing, not even the rear left tire. (Of course I'm sure he had to remove the fill plug, otherwise he's a magician, lol). I started noticing the issue the evening after the fluid change so it's just hard for me to believe that's a total coincidence...

I just want to think about this and get as many ideas as I can so that when I have that dealer appointment on the 18th I can give them a lot to go off of; I want to avoid the dreaded "could not replicate" scenario... I will press the fact that I can demonstrate it for them.

 

Alright, the dealer had my car for a month, I had told them I wanted to address some TSB work, but that "My number one concern and the reason I came here is because of the clunking in the rear", they decided to instead "work" on the TSB for the fuel tank first, which involved nothing but waiting an entire month for parts with my car's driveline taken apart (as installing a new fuel tank, which the TSB didn't even require for "fuel tank hard to fill", involves dropping the rear subframe, which involves taking apart some of the driveline). When I dropped the car off originally, the shop foreman sat in the car with me and confirmed that he heard the noise, it was completely evident, but upon finishing with the fuel tank, my service advisor let me know that the clunk is "gone" and invited me to take another ride with the shop foreman (even though at first they couldn't replicate the condition without me). I was really surprised to find out he was actually right and it did seem like the noise disappeared; I drove in circles in the lot for what must have been almost 10 minutes and I couldn't get the noise to come back when letting off the throttle, so I just assumed that I was right that there was slack somewhere in the driveline and that them re-doing the driveline to do the fuel tank fixed the problem inadvertently... So I drove it off the lot, I drove the car a bit harder on my way to work and, of course, when I'm driving slowly into the parking structure, the clunk comes back. Since I drove the car off the lot and they finished the paperwork, the car will no longer be covered by CPO warranty as it ended October 30th. The problem is now no better, but no worse. I'm sorry if anyone was waiting to see what the outcome would be but in this case it's absolutely nothing... Sucks.

At least I saved about $5,000 for the fuel tank installation... I did talk to the manager about their logistics, I was really bothered by the fact that they wouldn't take advantage of the driveline being apart to inspect every piece of the driveline, I'm not sure what's my fault and what's not at this point but, I'm sick of worrying, I'm just going to drive on it until something fails, hopefully it never turns into something serious. If anyone has any ideas I'm all ears, maybe eventually I'll get some jacks and sort it out the diagnosis myself... Or nothing's wrong and it's just some kind of quirk, who knows?

 

I'd say that, since you reported the fault before the expiry date and the fault still exists, it should still be covered by the warranty.

 

I would agree with this statement ☝️. The fact that they waited your car out until the CPO expired does not absolve them from addressing an issue you brought to them prior to the expiration. I would go back to that dealer and tell them to fix it. They should even have a record of date and mileage when you brought the car in and a list of "Customer" ="you" complaints.

Also, back in the original few posts, there was some discussion about the Motul fluid. I put that in my car (MOTUL GEAR 300 75W-90 1 LITER) when I changed mine and it has worked flawlessly with no noise... and including some 1/2 mile airstrip racing.

From the Motul site, this IS compatible with the F-Type E-Diff..Just as a point of clarity.

Good luck with your issue OP.

DC

This is what is presented after entering F-Type R AWD

 

Thanks DC for the heads up on the Motul!
Just this morning I went web shopping for Castrol BOT 720 and surprise surprise no-one but no-one in Oz sells it and it would cost well over $100 AU with postage to get a whopping 1 litre from OS.
I checked for the Motul Gear 300 and there are quite a few Oz sellers so I just bought 1 litre for $49 including postage.

 

Great. Just so you know...It is a b%@* to find here as well...other than going to s ***********.

Here is a link to the website that you can enter your vehicle and get the recommended product. LINK HERE

Someone also mentions Ravenol...I use that is some of my Porsches as well. and they make great products as well.

Good luck.
DC