I've got a bunch of gear oils on hand and would prefer to not spend what I see as probably unnecessary $45-60+ on more gear oils.
My Explorer is having some ticking problems. I'm not sure what the issue is. It has 203,000 miles. It's the one vehicle I'm just not confident in the lifespan.
I drive this ~1,000 to 2,000 miles per year, all short in town trips. I'm hopeful in forecasting 10 more years on this vehicle, so that's 10-20k miles. I have already spent far more than I wanted on maintenance on this so I'm really not wanting this to be a money pit. Cutting corners where I think I safely can without harming it.
I'm in Idaho where winters reach sub-zero and summers reach over 100 on a regular basis. I have read a lot about the benefits of a heavier weight on these Fords, and many go to 75w110 or 75w140 with good results.
I am considering using one type or a mixture of the following of what I have on hand.
3.5 Qts of Valvoline and Quaker State conventional 80w90. All GL-5. (This is a "free" option, no other applications)
8 Qts of Chevron ESI Isosyn 85w140 GL-5 (I think it's conventional, but unsure). (This is a "free" option, no other applications)
8 Qts of Valvoline 75w90 synthetic. ($15 per Qt retail) (I have 5 other vehicles to service that all require this weight)
I'm thinking either use up the 80w90 since I have no other applications for it. Or mixing it, 1/1 with the Chevron 85w140 to get something like a 85w115, or mixing it 1/1 with the Valvoline synthetic to get a blend around 80w90. I considered buying some Valvoline 75w140 and mixing 1/1 with the 75w90 on hand, to get me something like a 75w115 weight.
I wrote Valvoline and Chevron with my plan and proposal and awaiting any responses on mixing these.
I should note the two other vehicles I'm considering this option for are a 2005 Mercury Grand Marquis (my primary sedan) and my 2002 Ford Crown Vic (my secondary sedan). I alternate driving these. Both very well maintained, I just like the Mercury better. I expect at least another decade from each of these at ~1,000 to 2,000 per year on each as well. I am sorta looking for an excuse to use up these gear oils sitting on the shelf. So if they or a combination of them will work for this/these applications I'm leaning toward that.