Hi all,
Ahead of posting the full detail information on the engine rebuild, I just thought it would be worthwhile putting a little bit of history down for the car and it’s use over the previous 12-18 months, so as to provide a little food for thought for others in the forum.
1. This is my daily drive, and up to the point of failure, has covered 65450 miles under my 3yrs and 3 months of ownership.
2. It has both upper and lower pulleys upgraded, cold air induction kit, larger charge cooler and a performance map by Viezu, and was tested on their dyno producing 450hp and 441 Ft-Lb in June 2022
3. The car currently has 100684 recorded miles
4. In the period of my ownership, I’ve never had cause to top up the oil between services, as it had always remained staunchly stable at the mark it was handed back to me from the servicing garage right through to the next service
5. My daily driving use is very mild in terms of stress on the engine, with the majority being 50+ mile journeys sitting at 75-80mph on the motorway, and only being opened up on the occasions of working at a weekend, which sees less traffic on the roads and affording a little bit more latitude to give the engine a decent run
6. I only fill with Super Unleaded, and use a shot of Redex injector cleaner in every 3rd tankfull of petrol
7. I like to think I’m a conscientious and fastidious hands-on home mechanic, and with the recorded mileage increasing significantly in my ownership, and since the 84-month service undertaken at Jag (76157 miles 19/07/24), I have made the choice to undertake all of the standard servicing myself which provides a cost benefit to me, but is also something I thoroughly enjoy doing
8. Based on the 84-month service, the next oil service (according to Jag 16k schedule) would be needed at 92157
9. My next items on the service requirement list were both the transmission and the rear diff, both completed at 81057 on the 07/09/24, with all parts and fluids obtained via British Parts
10. My first oil service fell in January this year, with this being completed at 90992 (1165 miles inside JLR prescribed mileage), with filter from Berkshire Jag Components https://www.berkshirejagcomponents.com/products/f-type-oil-filter-c2d3670 coupled with 7.5ltrs of Mannol Legend Ultra 0W-20 - 7918 ILSAC GF-6A Premium Bi-Synthetic Engine Oil meeting Jag specification STJLR.51.5122
11. As the car is getting older, I had already decided to reduce the oil service frequency down from the 16k manufacturers regime to 10k intervals
12. In February 25, I booked to attend the JEC track day at Silverstone
13. On 30/03/25, I undertook brake maintenance in advance of the track day, and this saw rear discs renewed together with EBC Yellow Stuff pads being installed front and rear to provide the additional stopping capacity expected at such a high speed circuit as Silverstone.
14. In preparation for the JEC track day at Silverstone 12/05/25, as advised, I topped up all fluids to the max levels the night before to ensure maximum protection available to the engine whilst being subjected to the higher stresses of track use
15. The day at the track was a great event, with the car performing strongly (mechanically) all day long, with 185 miles of circuit lapping clocked up by the end of the day
16. During the track day the car suffered with a persistent TPMS issue, which on one occasion caused the car to go into limp mode, but we found this only occurred when the car was in Sports Auto mode, and never happened when the paddle shifts were being used – it was very odd, but as we’d found an effective work around, we just continued pounding the circuit, and gave it no further thoughts
17. For anyone interested, the overall on-track stats for the day were 185 miles covered (9 stints of 15-20 laps ea), at an average speed of 63mph, with an average mpg of 6.4!
18. At no point during the day did we witness any smoke or other indications that might lead us to suspect something was amiss or giving out within the engine
19. Since the track day, (due to a lack of work for me), the car has only seen minimal use, covering just 2254 miles over the 3 months to 08/08/25, but this included 9 days of me working at distance, commuting 210 miles each day, leaving only 364 miles of other local driving to the date of failure
20. On the way into my current project on 08/08/25, driving along a 50mph limit single carriageway A-road, and leaving an island at 30mph or so, there was a sudden and prominent thrashing mechanical noise from the engine, which bore all the hallmarks of a bottom end failure
21. There were no warning lights or notifications whatsoever recorded on the dash, the engine temperature was stable and all remained this way as I limped the car the 1.5miles left to travel to my place of work, where it was then parked up to assess what had happened
22. First check was the oil level – this was now reading 1 unit below minimum on the digital scale, which definitely suggested an oil starvation issue had affected the engine
23. I contacted RAC to come and assess the car themselves (as it would need the services of a flat bed to be recovered to wherever it was to be repaired) and on start-up they confirmed the same bottom end crank / rod knock that I’d suspected
25. The engine kept turning, and there was no adverse internal failure to cause block damage
26. The car was dispatched to QP Online arriving with them pm on Thursday 11/09/25, and work to remove the engine commenced from Monday 15/09/25
27. First thing was to drain and measure the oil remaining in the engine – this was all of 2.75ltrs out of the 7.75ltrs or thereabouts that would have been present when fully topped off immediately before the track day
So, with the rebuild now getting under way, there are a couple of issues that spring to mind, that I’d appreciate comments on:
1. Was the engine already suffering the early aspects of bore and / or piston ring wear (prior to the track day), and hence the high consumption of oil, and was the track running essentially the start of the end?
2. Why did the car not raise any warnings over the period of 3 months as to the ever-decreasing volume of oil left in the engine?
3. My online research into what warnings might or should have been raised by the car have thrown up a whole myriad of possibilities as below:
a) None at all
b) It should have identified anything below the minimum volume needed to protect the engine (does anyone know what this minimum volume is?)
c) Notifications on the dash instructing specified volumes of oil to be added immediately!
I genuinely have no idea which of these is correct or relevant for my particular car and fitment level (presuming this could cause a variance in fitment specification at manufacture)
4. Did my selection of Mannol oil over a more expensive / reputable brand name contribute to / accelerate the engine failure (It may be fine for day to day low stress use, but has it failed it’s job when asked to cope with the higher demands and heat created by the track running despite having the JLR specification requirements covered off?)
5. Would I have had a different outcome using Mannol Legend Formula C5 0W-20 7921 ACEA C5 Bi-Synthetic Engine Oil – again made to the JLR 51.5122 spec (no idea what the differences are between the 2 products!)
6. Following the rebuild, should I change my oil selection going forward (having just purchased a further 20ltrs in advance of the 3 swift oil changes that I’ll do at 500, 1000 and 2500 miles post rebuild to ensure all possible running in debris is swiftly removed from the oil system!)
With the car already over 100k, and my intention to continue to drive it for many years to come, the engine failure is more of an inconvenience rather than a tragedy, (the overall financial cost is the biggest issue as it's come as an unplanned bit of maintenance) as in 20k the engine would have needed to be pulled for new timing chains etc anyway, so taking the extra cost now for all of the additional engine work over and above the timing chains isn’t really such an issue on the proviso I essentially get an as ‘new’ remanufactured engine back in the car, which should then mean it would be good for at least another 100k + before anything of this magnitude is required again (maybe more if the periods between oil services are reduced!)
I'll post separately detailing the full reconditioning of the engine, including all of the photos & videos that have been provided by QP as they have progressed the work - the before & after shots are both scary and amazing in equal measure!
Ahead of posting the full detail information on the engine rebuild, I just thought it would be worthwhile putting a little bit of history down for the car and it’s use over the previous 12-18 months, so as to provide a little food for thought for others in the forum.
1. This is my daily drive, and up to the point of failure, has covered 65450 miles under my 3yrs and 3 months of ownership.
2. It has both upper and lower pulleys upgraded, cold air induction kit, larger charge cooler and a performance map by Viezu, and was tested on their dyno producing 450hp and 441 Ft-Lb in June 2022
3. The car currently has 100684 recorded miles
4. In the period of my ownership, I’ve never had cause to top up the oil between services, as it had always remained staunchly stable at the mark it was handed back to me from the servicing garage right through to the next service
5. My daily driving use is very mild in terms of stress on the engine, with the majority being 50+ mile journeys sitting at 75-80mph on the motorway, and only being opened up on the occasions of working at a weekend, which sees less traffic on the roads and affording a little bit more latitude to give the engine a decent run
6. I only fill with Super Unleaded, and use a shot of Redex injector cleaner in every 3rd tankfull of petrol
7. I like to think I’m a conscientious and fastidious hands-on home mechanic, and with the recorded mileage increasing significantly in my ownership, and since the 84-month service undertaken at Jag (76157 miles 19/07/24), I have made the choice to undertake all of the standard servicing myself which provides a cost benefit to me, but is also something I thoroughly enjoy doing
8. Based on the 84-month service, the next oil service (according to Jag 16k schedule) would be needed at 92157
9. My next items on the service requirement list were both the transmission and the rear diff, both completed at 81057 on the 07/09/24, with all parts and fluids obtained via British Parts
10. My first oil service fell in January this year, with this being completed at 90992 (1165 miles inside JLR prescribed mileage), with filter from Berkshire Jag Components https://www.berkshirejagcomponents.com/products/f-type-oil-filter-c2d3670 coupled with 7.5ltrs of Mannol Legend Ultra 0W-20 - 7918 ILSAC GF-6A Premium Bi-Synthetic Engine Oil meeting Jag specification STJLR.51.5122
11. As the car is getting older, I had already decided to reduce the oil service frequency down from the 16k manufacturers regime to 10k intervals
12. In February 25, I booked to attend the JEC track day at Silverstone
13. On 30/03/25, I undertook brake maintenance in advance of the track day, and this saw rear discs renewed together with EBC Yellow Stuff pads being installed front and rear to provide the additional stopping capacity expected at such a high speed circuit as Silverstone.
14. In preparation for the JEC track day at Silverstone 12/05/25, as advised, I topped up all fluids to the max levels the night before to ensure maximum protection available to the engine whilst being subjected to the higher stresses of track use
15. The day at the track was a great event, with the car performing strongly (mechanically) all day long, with 185 miles of circuit lapping clocked up by the end of the day
16. During the track day the car suffered with a persistent TPMS issue, which on one occasion caused the car to go into limp mode, but we found this only occurred when the car was in Sports Auto mode, and never happened when the paddle shifts were being used – it was very odd, but as we’d found an effective work around, we just continued pounding the circuit, and gave it no further thoughts
17. For anyone interested, the overall on-track stats for the day were 185 miles covered (9 stints of 15-20 laps ea), at an average speed of 63mph, with an average mpg of 6.4!
18. At no point during the day did we witness any smoke or other indications that might lead us to suspect something was amiss or giving out within the engine
19. Since the track day, (due to a lack of work for me), the car has only seen minimal use, covering just 2254 miles over the 3 months to 08/08/25, but this included 9 days of me working at distance, commuting 210 miles each day, leaving only 364 miles of other local driving to the date of failure
20. On the way into my current project on 08/08/25, driving along a 50mph limit single carriageway A-road, and leaving an island at 30mph or so, there was a sudden and prominent thrashing mechanical noise from the engine, which bore all the hallmarks of a bottom end failure
21. There were no warning lights or notifications whatsoever recorded on the dash, the engine temperature was stable and all remained this way as I limped the car the 1.5miles left to travel to my place of work, where it was then parked up to assess what had happened
22. First check was the oil level – this was now reading 1 unit below minimum on the digital scale, which definitely suggested an oil starvation issue had affected the engine
23. I contacted RAC to come and assess the car themselves (as it would need the services of a flat bed to be recovered to wherever it was to be repaired) and on start-up they confirmed the same bottom end crank / rod knock that I’d suspected
25. The engine kept turning, and there was no adverse internal failure to cause block damage
26. The car was dispatched to QP Online arriving with them pm on Thursday 11/09/25, and work to remove the engine commenced from Monday 15/09/25
27. First thing was to drain and measure the oil remaining in the engine – this was all of 2.75ltrs out of the 7.75ltrs or thereabouts that would have been present when fully topped off immediately before the track day
So, with the rebuild now getting under way, there are a couple of issues that spring to mind, that I’d appreciate comments on:
1. Was the engine already suffering the early aspects of bore and / or piston ring wear (prior to the track day), and hence the high consumption of oil, and was the track running essentially the start of the end?
2. Why did the car not raise any warnings over the period of 3 months as to the ever-decreasing volume of oil left in the engine?
3. My online research into what warnings might or should have been raised by the car have thrown up a whole myriad of possibilities as below:
a) None at all
b) It should have identified anything below the minimum volume needed to protect the engine (does anyone know what this minimum volume is?)
c) Notifications on the dash instructing specified volumes of oil to be added immediately!
I genuinely have no idea which of these is correct or relevant for my particular car and fitment level (presuming this could cause a variance in fitment specification at manufacture)
4. Did my selection of Mannol oil over a more expensive / reputable brand name contribute to / accelerate the engine failure (It may be fine for day to day low stress use, but has it failed it’s job when asked to cope with the higher demands and heat created by the track running despite having the JLR specification requirements covered off?)
5. Would I have had a different outcome using Mannol Legend Formula C5 0W-20 7921 ACEA C5 Bi-Synthetic Engine Oil – again made to the JLR 51.5122 spec (no idea what the differences are between the 2 products!)
6. Following the rebuild, should I change my oil selection going forward (having just purchased a further 20ltrs in advance of the 3 swift oil changes that I’ll do at 500, 1000 and 2500 miles post rebuild to ensure all possible running in debris is swiftly removed from the oil system!)
With the car already over 100k, and my intention to continue to drive it for many years to come, the engine failure is more of an inconvenience rather than a tragedy, (the overall financial cost is the biggest issue as it's come as an unplanned bit of maintenance) as in 20k the engine would have needed to be pulled for new timing chains etc anyway, so taking the extra cost now for all of the additional engine work over and above the timing chains isn’t really such an issue on the proviso I essentially get an as ‘new’ remanufactured engine back in the car, which should then mean it would be good for at least another 100k + before anything of this magnitude is required again (maybe more if the periods between oil services are reduced!)
I'll post separately detailing the full reconditioning of the engine, including all of the photos & videos that have been provided by QP as they have progressed the work - the before & after shots are both scary and amazing in equal measure!
