Rotella T4 15w-40

[Tarantulahed504]

as the thread title states; I got my hands on some rotella T4 15w-40 diesel oil for cheap. I was hoping to use it in my 78’ GS750. I’m located in New Orleans so I don’t have to worry about cold weather riding conditions. More like 90-100F for almost half the year


thanks for the space
Andrew R

[Nessism]

There are about 1000 posts here from people happily using Rotella T4.

[Tarantulahed504]

I searched a bunch and found a lot about the 5w not the 15w. Was just wondering if the viscosity range was too high. But like I stated I’m in hot n humid New Orleans on an air cooled

[Downs]

Manual recommended 10W40 IIRC, so a 15W40 especially in a warm climate should be good to go. I run it in all of my bikes and my Jeep. Diesel oil is still allowed to have a healthy ZDDP additive package so on older flat tappet engines and motorcycles it seems to do well. AFAIK Rotella used to hold a JASO-MA certification and the only reason it was dropped was because they didn't submit for it.

[Tarantulahed504]

Thanks Downs.

[LAB3]

The top end in my bike tends to get louder in hot weather, I just might try a 20w50 sometime just to see if it helps change that. Long story short, don't sweat the 15 vs 10.

[bwringer]

Manual recommended 10W40 IIRC, so a 15W40 especially in a warm climate should be good to go. I run it in all of my bikes and my Jeep. Diesel oil is still allowed to have a healthy ZDDP additive package so on older flat tappet engines and motorcycles it seems to do well. AFAIK Rotella used to hold a JASO-MA certification and the only reason it was dropped was because they didn't submit for it.

I use the Rotella T4 15W-40 year round in Indiana.

The fresh bottle in my garage says JASO-MA, and so does every other bottle I've seen on the shelf lately.

[salty_monk]

I've used that & the full synthetic. No problems. You may get some pull against the clutch in first gear on initial start (i.e. there may be some "drive" there with the clutch all the way in but not enough that it affects anything, just enough that you'll feel it. That is normal).

Currently to "run in" the GS1100 I'm using a high quality Castrol Diesel dino oil... that's working too. (mostly because my local O reilly had a gallon of it reduced down to $3.50.. Left over stock apparently and it's coming out again pretty soon).

[hannibal]

Plus one for the T4 15W40. I'm obsessed with it and grab a gallon when I see it at a good price.

[GSthou]

Question to the UK GS owners with no availability of Rotella T4 in UK, what engine oil alternative do you use in your GS

[Grimly]

If I was looking for a synthetic Shell right now, I'd buy some Helix 5w40 - gas-to-oil synthesis and very good stuff, but I don't know how well it copes with shearing, which these gearboxes do to the oil.
Ignore the usual greedy sods selling it, you can find it on Amazon for a decent price.