Hello all.

Something for the brainy boys to ponder. The car is a 1991 300CE-24 Sportline with 722.5 auto box.

The car now has 360 K Kms. The gearbox has always worked but has had the odd 4/5th issue that now appears to be resolved, temporarily at least.

The filter and oil were changed 40 K Kms ago and I assume my local garagiste used a genuine MB filter. Oil used was Renaultmatic D2.

Since that, the only new issue has been that of an intermittent refusal to engage reverse. Symptoms as follows:

Car cold, reverse always fine. Engages in less than a second with a positive feel.

Car hot after, say, 30+ km run and reverse is, again, reliable. I have no worries when we're on a long journey.

Also, when working reverse is fine and strong. The box appears to exhibit no slipping of any sort. When it works, it works very well indeed.

However, after a shorter journey when I assume things are warm rather than hot, reverse MAY fail to engage. Some days all will be well but increasingly often it just sits there. There is a suggestion of a change in engine revs as it attempts to engage reverse but then nothing. The only answer then is to switch off and wait for a temperature change (I think). After that, if reverse engages, all is well until the next time.

My current plan is to do another oil/filter change, ensuring that the torque converter is drained too. I cannot be sure this happened last time.

To recap, once hot the box is performing really well, better than ever really. Quite rapid down-changes, strong engagement of all 5 gears, positive up-changes and a strong, positive reverse when it engages.

If anyone has any suggestions (aside from the high priced ones!), I should be most grateful.

All the best to everyone.

RayH