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[DAV8]

Hi all, calling all auto gerabox experts (type 35) When I get the engine to operating temp then off for a run, and the gerabox still cold all the changing through the gears is okay, when everything else gets hot (the gerabox fluid) I get an occaisional klonk usually when it drops into 2nd mostly when going down hill and the upshifts can be a bit rough although this is not too bad, any advice will be appreciated. Thanks
DAV8
Dave

 

[harveyp6]

If the clonk on the downshift is on the 2-1 shift, (not the 3-2 as would be implied from reading your post) then that sounds like the pressures are too high, which will make the upshifts late and harsh, give harsh engagement, and give you that clonk. You could try adjusting the cable, roadtesting in between adjustments. You will need to screw the adjuster on the outer cable towards the carbs. You're aiming to get the inner cable so that there is no slack, but it's not so tight that it holds the valve open inside the box, which would appear to be what's happening at the moment.

 

[DAV8]

Thanks Harvey, I'm sure that the klonk on the downshift is from the 3 to 2, I have looked at adjusting the cable but it doesn't look to clear on how to adjust it!, as you probably know these boxes tend to leak somewhat and I seem to be forever topping up the level, could a low level fluid cause any of this?
Best Regards Dave

 

[harveyp6]

I'm sure that the klonk on the downshift is from the 3 to 2,

If that is the case, then maybe it's a front band or servo problem. Are there any problems with the 1-2 upshift?

I have looked at adjusting the cable but it doesn't look to clear on how to adjust it!,

There should be a threaded ferrule on the outer cable, and this needs to be screwed into the bracket to reduce the pressures.

as you probably know these boxes tend to leak somewhat and I seem to be forever topping up the level, could a low level fluid cause any of this?

Low fluid level can cause all sorts of problems, so check the level and set it correctly before doing your roadtests and you may find once you've done that all the problems disappear, and if not at least you're starting from a known point. The fluid level should be set correctly as a matter of course before doing anything.

 

[DAV8]

Hi Harvey, generally the 1 - 2 upshift is not bad (all the changes are best when the box and fluid are cool) but I'm fairly sure the klonk is on the 3 - 2 downshift, the fluid colour is as it should, so, I will have a look at the level again, check the adjustment on the downshift cable, all after Christmas now and with decent weather.
Have a good Christmas and New Year
Best Regards
DAV8 Dave