2004 Jaguar XJ8 Mobil 1 15w50 ... need some advice

Status
Not open for further replies.
Originally Posted By: wolfc70
A slight rattle at start up is usually one of the indicators that the guides are worn/broken. I am not 100% sure of the exact model years affected, but I believe I am close.


The 4.2 liter engines have the updated chain guides. All US market 2004 MY cars had the 4.2 engine. 2004 MY production actually began in 2003, and some of the late 4.0's might have had the latest iteration of the chain guides

You are correct about the earlier cars, though. The chain tensioners were a weak point on the earlier 4.0 engines.
 
SubLGT , it recommends no specific oil. It has a temperature range saying (off the top of my head) if temperatures exceed 10 below zero f to use a 5w30... and can use up to ,again not positive its been a while since I read the owners manual, up to a 10w40...

well I just got finished changing the oil and drove the car around for a few. Feels good and the motor is a bit quiter. Acceleration is just as smooth and ferocious as ever..

I think its actually better then what I had, maybe because its fresh ? Or maybe placebo effect ? Not sure but I am happy for right now.

Im going to go on a 30 mile highway cruise right now to pick up my wife and Ill judge it then, give it some time to wakeup too.

Thanks everyone for the information and timely responses, I DO appreciate it. Check back in a few hours...

-Vic
 
Came back from that drive, the car was running exceptionally well. So as of right now I feel a made a good choice with this oil, especially since from monday on its going get very hot.

Thanks for the help !

-Vic
 
Originally Posted By: SubLGT
StrateLOSS, what oil viscosities are recommended in the Jaguar owner's manual?


For the 2004 MY XJ-8, the drivers handbook states that between -22F and +122F, it requires API SJ/ILSAC GF-3 as a base, and viscosities of 0w-30, 5w-30 (preferred), 0w-40, and 5w-40 may be used.
 
yes I did, drives good and seems to accelerate nice and smooth. I am waiting for that uoa testkit to come in and will sample this oil before drain.

this is my first time not using 5w30 so I personally dont oil gives me desired performance. I read some more and "heard" this oil will shear to a 5w50 quickly, if thats possible IDK. and thanks to nate this oil is almost as thin as a thick 40 so time will tell.
 
Where is the audie dude? Doesn't he know a guy who says mobil 15w50 is bad swill? Anyhow I have used mobil 15w50 in my land rover discovery when it was having cooling system issues. Now that everything is fixed I used M1 TDT 5w40. Mobil 1 15w50 is great oil and has higher additive levels than most HDEOs.
 
Last edited:
I used the M1 gold cap for a few years. I`ve always thought it was one of the best oils ever made. You made a good choice!
 
thanks for the reassurance guys...

my cooling system is fine, al gauges read normal,coolant is fresh, t-stat goes on, no noise from pump, system is pressurized. it just seems like the engine bay is normally supposed to get hot like this, which had me thinking I was cooking the oil. I did topoff 3/4 qt after 1500 miles on the PP which I found odd. IDK if it was me not filling to full or it burned ( engine hadnt burned oil with my previous 7k miles of ownership ) or it evaporated. IDT we will ever know that lols


did the 15w50 help with underhood temps? although I do know you cant tell for certain without all types of field tests but I figure Id ask.


I did read where audi junkie says its a pretty bad swill... but I have no idea what swill is hehe

he is critical of M1 ,me personally I have no bias towards any oil. Just want something that works.. On my fathers 2000 Jag VDP I used to get him mobil 10w40, and on y previous honda I used 5w20 so I do like mobil.

Audi junkie did bring up valid points on mobils wear numbers though, and it had me hesitant to go to mobil again. But after carefull judgement I went ahead with it after learning that uoas only read particles of xxxx microns and nothing bigger, so really it shouldnt be a thing. Thanks everyone and keep the comments coming, I get pretty bored and this is entertaining

-Vic
 
Originally Posted By: StrateLOSS
. did the 15w50 help with underhood temps? although I do know you cant tell for certain without all types of field tests but I figure Id ask.


mechtech2 answered that question awhile back - "Oil temperatures should go up with the thicker oil. It drags more, insulates parts more, and flows less. More heat is expected."
 
mechtech2 answer if this oil helped on his landrover ?

on this motor it seems normal operating temp is very hot, so the 15w50 should hold up better. Seems to be doing verywell up untill now.
 
I`ve always thought thicker oil would keep the engine cooler by providing a thicker oil film,reducing friction (more space between moving parts),and especially since thicker oils are always recommended via FSM with high performance hotter running engines..........to keep them cooler?
 
Last edited:
You have had good empirical results with the oil.
Nothing else need be said.
It is not hurting your engine in any way, and the high HT/HS may be helping it.
Do not run this through a NY winter, however.
Check my sig.
Nothing wrong with M1 15W-50.
 
Nice thanks for the response !

Also I wont be using this in the winter, by late october or november I will change it out for 0w40 or 5w40, Ill decide then.
NY weather is tricky, sometimes it doesnt start to feel cold at all untill after haloween, and sometimes its freezing way before it. We dont have a set standard when it comes to weather, all the pollution and tricky location really make the temps unpredictable.

I will no longer judge OCI by mileage, Im just going to go bi-annual. Once for the warm months and once for the cold months. I am using synthetics and Jaguars specs 10k OCI on non synth. My est annual mileage is under 10k so I am safe there.

and man, why the 50 in the Hondas ? Just curious
 
Originally Posted By: aquariuscsm
I`ve always thought thicker oil would keep the engine cooler by providing a thicker oil film,reducing friction (more space between moving parts),and especially since thicker oils are always recommended via FSM with high performance hotter running engines..........to keep them cooler?


Thick oils are recommended in hotter running engines because they will still be thick enough at high temps. Just look at viscosity plots oils get thinner with higher temps some oils will be too thin to provide proper lubrication at high temps. Thicker oils will raise temps a bit.
 
Status
Not open for further replies.
Back
Top Bottom