so recently i bought Focus MK4 my2020 and it run great on 81000km, after 3000km car started to shake it on lower RPM (it is very noticable on 8th gear, 80km/h, 1100rpm's - kind of grandpa's driveing the way i like it!) the oil in the transmission hasnt been changed yet so i get that that might be the problem and i will service the gearbox.

one thing that i can't find is what oil goes in transmission. it's an 8F40 gearbox and I found that one sight that sells spare parts says "oil type for: 8F35 / 8F40 8 / 1, and CASTROL Transmax, Multivehicle 15D746, and EUROL ATF 6700, Automatic E113653-1L are supported to this transmision" and later on I found that 8F35 uses Mercon ULV ATF. now i am completly confused of wich i should get. Price difference is HUGGGE!, naturaly becouse of my income i would prefer that service cost is cheaper to be honest.

Can you tell me with 100% clarity wich oil goes into transmition (CAR IS NOT UNDER WARRANTY) and FORD official service gave me the answer that they don't have service interval for that model of transsmision wich i found to be confuseing. NO OIL is for lifetime.

Service man told me "on the side" that he think this transmission is for arround 120tkm to go and then change it completly wich is 1/2 the cost of the car in my country.

what is the possible reason for the tremmor/shakeing of the car on low RPM's (high rpm is all good and driveing is awsome in SPORT mode)

 

Help and if you can, please elaborate your answer.

thanks in andvance

N00b new ford focus owner!

I would be surprised if the fluid is NOT MERCON ULV but still could be MERCON LV

I know they changed 6F15 to ULV on Ecosport, but don't think they did on Fiesta and I don't think they did on 6F35 either (and 8F35/40 is based on 6F35)

There should be a label on the transmission, somewhere, telling you what fluid it needs.

You won't be able to drain all the fluid, about 50%, so drain and refill, then, if you want to, drain and refill again after 500 miles

I know Focus can suffer with low voltage issues, make sure the battery is good and increase the battery monitoring to 95% using FORScan

Get the software updated in the PCM (and TCM if it has one, it may be combined) as it sounds like a software issue as it doesn't do it in Sport mode