Urgent gearbox help

[Kenny535d]

Hey all

cars in for a box replacement. The mechanic knew the car the box was from and has driven that car just before I bought the box. 
 

it’s all in mine now but only works in reverse. No forwards gears. The clutch pressures etc are all ok and there no fault codes. 
 

currently stood 70 miles from home with a car that only goes backwards. 
 

any ideas before I need to put the old knackered box back in? 

[Greydog]

Oh no, that car is testing you Mate

The box was working OK? What happened were you moving and lost drive? Or had you stopped and lost drive when you restarted?

As long as the shifter mechanism is OK (worth checking) my guess would at a Mechatronic's unit failure of some kind, either a seal or a break in the loom or the unit it's self. Try unplugging the loom (without power it should be in Limp Mode) and re-connecting just in case? 

Fingers crossed for the simple fix Kenny

Dave

 

[Kenny535d]

It’s most definitely testing my patience lol. 
 

the boy from The garage called me saying it wouldn’t select any forward gears. Only reverse. I got back to the garage and he Started to drain the fluid to remove it to put the old one back on and realised there wasn’t enough oil in it. The tc was done too so took more oil that just the service kit I think. 
 

once it was topped up it’s been fine since, well I say fine, getting a tiny bit of slip before it engages. Think the oil may have settled a tad too low overnight/leaked. Going back to have it checked, but is completely night and day to the old box, the oil was like tar. 
 

it was not a nice afternoon after spending the best part of 1k to have this all done and get a call saying it’s not working. Lol. Thankfully and hopefully it’s just needing a little too up. Poor lad in the garage, his face was almost the same colour as mine at the thought of having to put the old box on, hats off to him for persevering and finding the issue
 

 

[Greydog]

Deep breath Pheww

Sometimes it's simple things that cause us the most grief. Go through the adaption process a couple of times plus check levels after a few days running plus add a tube of Dr Tranny

Dave

[Kenny535d]

On 11/25/2021 at 6:38 AM, Greydog said:

Deep breath Pheww

Sometimes it's simple things that cause us the most grief. Go through the adaption process a couple of times plus check levels after a few days running plus add a tube of Dr Tranny

Dave

Hey dave

So I’ve been back today and the gearbox needed another half litre to top it off, rock steady revs but still get a touch of slip in the first coupe gears sometimes. Would this dr tranny help that?

At the same time I’ve had a couple of thermostats added. I’ve read online too many stories about new stats failing shortly after use so I’ve opted for the in hose ones for box and engine. I know they aren’t oe spec but the temp readings are pretty much good. Mpg is back up to where it was during the summer. 
 

The hidden dash temp does rise a fair bit over the 92. Promptly returned to 88 though within seconds, can tell with the temp reading when the stats open up. I’ve released any pressure in the tank earlier so will see what’s what tomorrow. 
 

 

[Greydog]

Morning Kenny

Yes Dr Tranny really does work, takes a few miles to get thoroughly mixed in  One of the only "Snake Oil" fixes I have tried 

My X5 I fitted an external trans oil cooler with stat and engine wise I changed the main engine cooling fan for an electric one with an in hose stat. I did this as I would be towing a couple of Fat Horses in a trailer so wanted to make sure it all stayed cool.

Dave