Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[IrishKenCJ7]

Hi all.
So the recommended oil is 10w30. What are ye using. I can't find it online in UK or ireland.  I found some mineral oil but I believe I should be using semi synthetic. Halfords only do motorbikes 4 stroke oil.

Anywhere online I can order 6 litres.

Thanks
Ken

[gazjeep]

Not sure where you have got 10w 30 from mate.

Have a look here http://www.birtydastards.com/frm/index.php?topic=8091.0

Always run our previous 4.0 XJ & our 1998 4.0 TJ on of 12 years on 10w40 Semi synthetic

Plenty of places online do 10w40 semi

[Brynjaminjones]

Not sure where you have got 10w 30 from mate.

10W30 I believe is what's recommended for normal climates in the manual and seems readily available in the US.
I've always had the same trouble finding it over here though so use 10W40 exactly as Gaz says.

I did try 5W30 for some time in both of our 4.0s as it's the other oil mentioned in my owner's manual, but it seemed a bit thin and I'd say they're a bit happier on 10W40. 

[gordy]

I bought and used this in my 99 XJ 4.0, 10-30w mopar engine oil. https://www.tuning-shop.co.uk/voyager-grand-voyager/5931-original-mopar-semi-synthetic-engine-oil-sae-10w-30-maxpro-5l-for-chrysler-dodge-jeep-plymouth-fiat-new-0603803750655.html

[scrw]

only evey used Morris 10-40 semi synth in my I6 enginges, did 350k miles between them all with no issues

[JamesH]

10w40 semi synthetic in every 4.0 and 2.5 I’ve owned has always been spot on

[bigjeepzj]

  and 5.2 V8 

[bonza]

Not sure where you have got 10w 30 from mate.

Plenty of places online do 10w40 semi

maybe like mine it has a sticker on the fill cap stating 10W-40. 2005 TJ

having said that I use 15W-40 semi syn and have for the past ten years. not too fussed about brand, usually use what ever's on special alternating between Castrol, Shell and Valvoline.

10W-30 for the first couple of years but the engine sounded a bit ticky, especially during the summer months so went for a slightly heavier viscosity. 200k later still runs well

as far as I can see, Jeep specifying 10w/30 was more trying to reduce internal drag of the mating parts and improve fuel efficiency (theoretically) rather than protecting internal engine parts

[harleykenn]

I've used 20-50 mineral oil in my '97 TJ 4.0 for the last nine years,  and in my YJ  before that
also my Wagoneer  and CJ 5 before that,   never had any problems with any of them,  I don't buy expensive oil either.