Going from a PAO to a Ester base MT oil

[Bill_W]

Suppose you have a OEM 75w90 GL-4 oil and go to Red Line MT-90. I understand ester base oil swells gaskets. Now down the road you want to go back to the OEM that is PAO. Will there be issues returning to a PAO?

 

[UG_Passat]

Redline isn't a pure ester base. It a mixture of Group IV PAO and ester.

 

[Olas]

Nitrile is resistant to esters so you could re-gasket if oyu were really concerned, but of all of the users on here that have used redline in the past I dont remember any who had a leak afterwards and attributed it to their oil. I think Redline probably research what gasket materials are out there and try to formulate oils that are safe for our engines. They wouldnt stay in business if they had a reputation for causing leaks!

 

[Bill_W]

Thanks... I have decided to go Red Line MT-90. But just curious if there might be issues returning to Mazda OEM oil later.

 

[Bill_W]

Originally Posted by UG_Passat
Redline isn't a pure ester base. It a mixture of Group IV PAO and ester.


Thanks, got info here...
https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=110076

 

[CT8]

Remember you are buying a finished product. A reputable company wouldn't sell dangerous to the component products.

 

[Wheel366]

Make sure that is the correct fluid for you. I used it in both my 95 pathfinder and 6sp 2004 a4 and when it was ~20 and below it was like shifting in mud until it warmed up. Went back to OEM fluid in the a4 and it was much better. Pathfinder, I got rid of before I changed fluid again.

 

[MolaKule]

Originally Posted by Bill_W
Suppose you have a OEM 75w90 GL-4 oil and go to Red Line MT-90. I understand ester base oil swells gaskets. Now down the road you want to go back to the OEM that is PAO. Will there be issues returning to a PAO?


The seal swell issue, when formulating combination PAO/ester combinations, were solved by 1975.

 

[PimTac]

Originally Posted by Bill_W
Originally Posted by UG_Passat
Redline isn't a pure ester base. It a mixture of Group IV PAO and ester.


Thanks, got info here...
https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=110076




That pretty old info.

 

[Bill_W]

Yep... old stuff, was worried about 100% ester base, no problem with a mix.

 

[Olas]

I found MT85 to be the best comprimise - MT90 was to notchy when cold and MTL was perfect when cold but would occasioanly crunch when hot. MT85 is perfect for me, but we all have different gearbox construction and different climates.

Dont worry about seal swelling

 

[Bill_W]

First replacement in my 2019 Miata. Seems to be popular, appreciate your comments.

 

[aquariuscsm]

Redline MT90 is the best you can get (for a 75W90 application). It definitely lives up to it's urban legend status.