FZJ80 Oil Choice? (April 2017) (2 Viewers)

[Funner]

Oil will not make old seals new but depending on the viscosity/polymers in the oil it may be less likely to seep past the old seals. As mentioned above the oil consumption in one of my 80's went down ~25% just with the change of the oil brand/viscosity (Chevron Delo 400 XSP 15W-40). This has been shown by others on the forum who switched for example to either of the Rotella 15W-40 oils from lighter viscosity oil. Of course at some point the valve stem seals will need to be replaced.

This has been an understood mud philosophy grounded in accepted fluid dynamics. Any thought about additional engine wear from higher viscosity fluids not getting where they need to be before they heat up and flow better? Similar to cold start wear?

 

[Batameez]

Oil will not make old seals new but depending on the viscosity/polymers in the oil it may be less likely to seep past the old seals. As mentioned above the oil consumption in one of my 80's went down ~25% just with the change of the oil brand/viscosity (Chevron Delo 400 XSP 15W-40). This has been shown by others on the forum who switched for example to either of the Rotella 15W-40 oils from lighter viscosity oil. Of course at some point the valve stem seals will need to be replaced.

Agreed that this is a realistic outcome, but I also wonder if it has more to do with these oils having a better additive package. The additives could be freeing stuck rings. This leads to decreased blow-by which could be causing oil to blow pasts seals. Just my theory at least.

 

[Kernal]

Yes, the Chevron specifically states that it was formulated to decrease oil consumption. IDK which magic chemicals/polymers they put in there but it did decrease oil consumption in my engine.

Either way, been discussed a lot in the past, using higher viscosity doesn't appear to be a problem in this engine, in fact higher viscosity oil is recommended in the owner's manual for Australia for example (see below).


From the FAQ section for the 1FZFE:

Australia Owner's Manual recommends the following oil viscosity, based solely on the performance requirements of the (1FZFE) engine, unrestricted by US CAFE fuel economy regulations:

Temperature
19 to 100F: 20W-50
14 to 100F: 15W-40
0 to 100F: 10W-30
-22 to 46F: 5W-30