hey everyone i was wondering what trans fluid everyone is running in their t5 trans and what gear oil everyones running in their 9inch rears
world class t5s use atf. an older t5 uses gear oil 90wt. do not put synthetic gear oil in a diff. its too slipery and gets squeezed out from between the gears and allows for gear failure. in my shop i use schaeffers oil. its not easy to get. i would recomend using lucas 85-140wt oil. its really sticky and doesnt get squeezed off of the the teeth when they mesh.
Sorry, slightly OT - What do you put in newer car differentials that orignally came with synthetic? According to the owner's manual come spring time it will be time to drain/fill my Chrysler 300's rear. Chrysler recommends synthetic.
If it specifies synthetic from the factory and nothing has been changed(gearset, clutches, etc) then run synthetic. When you upgrade to a higher ratio gearset and/or limited slip diff, you have to use what that manufacturer recommends. Mine recommended 80W-90 non synthetic with their compatible friction modifier. Some limited slip clutches are also not compatible with synthetic fluids. Newer Ford gearsets usually don't have fluid related failures unless it's contaminated, low or wrong weight. Most failures that I have seen on newer vehicles have been with bearings(improper preload) and LSD clutch failures from mulitple causes, but usually driver error and design as in the cases of Explorer IRS high efficiency fluid problems. That fluid has since been upgraded to the heavier weight synthetic. Bottom line is, use what the manufacturer of your parts (gearset) recommends and you're usually OK.
sence the manifactures switched to synthetic gear oil i have found the gear sets start making noise in about 15,000 miles. now there is no change in the design or materials used in differentals. i belive that the manifactures went to synthetic oil to try to lower there gross fleet fuel economy. now im sure they dont even get 1mpg increase but across fleet of vehicals every bit helps. i offer a warentee on my work. i fell confidnet in my warentee due to the quality of the oil i use.
