Slipping from 3rd to 4th

[mrbridger2]

My wife has a wonderful mk2 auto as her daily driver (during the summers) here in Norway. We’ve covered around 35000 trouble free kilometers with this car since 2007, but now the gearbox has started to develop a slipping problem when going from third to fourth. Is there a «quick fix» we could try so we could use the car this summer? I would rather pull the motor out during the winter months when it’s not in use.

Tore Hjellset
AutoClassic.no

[jockduck]

I thought someone else might have replied, When you say a slipping problem does the engine revs rise during the change and then normalize once 4th is engaged? this is called flaring, or does the gear slip in 4th when a heavy throttle is applied? Is there any difference in the performance when the engine is cold or fully warmed ? Have you changed the grade of oil used? If the gearbox is good in the other gears then the forward clutch is OK, if it only slips in 4th then the top/reverse clutch is suspect, how well does it go in reverse ?
I will catch up later if you can give answer the questions
Jock

[mrbridger2]

Thanks for your reply!

It’s flaring then. Once in 4th it’s all good. I’ve also experienced some weird noises when engaging reverse with a little throttle apllication. I’ve used mostly 15w40 and 20w50 over the years, but I’m using 10w40 motorcycle semi synthetic now.

Hope this helps?

[jockduck]

Hi again, has the flaring got worse since you started using the motorcycle oil? using 20/50 will cause flaring in cool weather because the oil flows slowly and delays the engagement of the top gear. If you are going to inspect the gearbox in the winter then you should find what is wrong, you could carry out some investigations now, you really need a copy of the official manual which gives a run down of how to carry out a stall test and pressure test to measure the operating oil pressure, a pressure test is one of the first things a automatic gearbox mechanic would do.
Jock