Mercedes vito 109cdi W639 2nd gear not smooth

[BlackC55]

I use 80W90 in mine as its old.

 

[Christosfazer]

I thought that this oil is for differential and not for the gearbox...
May i use red line mt lv 70/75w for the transmission?
I read that with this oil viscosity any crunches maybe dissapear
Is it true?

 

[Christosfazer]

Good morning to all,
i have read that the RED LINE SUPER LIGHTWEIGHT SHOCKPROOF® is the oil which dissapears the gear crunches!
Is anybody of you who tried this oil?
Is it right that the gears will stop crunches?

 

[andydown]

Hi there ive tried alsorts of different oils in my gearbox but t still crunches in second to its going to be new syncros they are about 40 quid per gear for MB

 

[Christosfazer]

Hello there,
I think that the problem is not on the syncros because when the transmission get warm the crunchy noise dissapears

 

[Phil1968]

I've had 5 Vitos from new in the last 20 years & the gearbox action was stiff in the Winter on all of them until the gearbox oil warmed up. Current one, a 2020 model is an auto though so can't comment on this particular one

 

[andydown]

iv just been doing dit of reasearch on the correct oil for the vito manual box ,well most modern boxes for that mater are using brass syncro ring , ,the oil reqirement for these type of boxes is GL4 or GL4+
this is because the GL5 oil has sulphur an phosporus additives in it to prelong gear life ,unfortunatly these additives corrode away the brass syncro rings ,hence the clicking and notchy gears