Have first and reverse no D

Yesterday whilst out and about my car D2 decided to go into limp mode after going up a hill.

It's recently had replacement cooler pipes for the gearbox so I firstly checked the oil level. It seems fine.

It drives in D from cold for about 5minutes and then just gives up but it will still let me drive in first and reverse.? Any ideas?

there are several things that go wrong with zf boxes one way clutch fail,and or 1 or more clutch packs burn out which can be seen with dirty burnt oil,disco 2 and p38 rr use ecu to change gears instead of mechanical govenor ,they usually arent to expensive to fix once removed and patially stripped ,i would thimk its more likely box problem rather than ecu,unlike a manual box you dont have one gear and clutch for each change but a collection of epicyclic units at rear of box and clutch packs at front and different combinations give different gears

ok what do you think to my problem i saw on ashcroft transmissions page that possibly a one way clutch might of failed? its been fine never had a problem until the oil cooler pipe came off and now its all replaced? theres no clunking and it does drive in 1st with no problems?

if the gearbox oil pump failed would that have the same symptoms as me?

you would have no drive and noise i seen very few pump failures that werent caused by bad fitting of torque convertorrs,usualy when you strip the front off these boxes you find 1 or more of front clutches burnt and or one way clutch

ok is that a simple fix? or does it need a rebuild as stated by ashcroft transmissions?

can usually done by competent person themselves with a little instruction , the parts in autos are either bust or good so quite easy to tell ,ive rebuilt or repaired quite a few so its difficult for me to how hard it may be from someone elses point of view,bot normally you wouldnt have strip completely

ok how come it lets me drive in D and goes through all the gears fine for 5 minutes from cold before it decides to pack up?

well it is possible sticking valves in valve block but this is rare and is usualy caused by other fault ie clutch plate debris ,clutch packs can be just holding till box warms up same with one way clutch when you hold the they are supposed to turn against each other one way and lock the other this can be intermittent and temperature effected ,prd321 are physicaly selected with cable operating shaft with xyz pack which lets ecu no what youve selected for position lights and ecu operation,as when in drive it decides on gear changes depending on road speed ,engine speed and throttle position ,may be ive read your post wrong and its this part thats faulty have you read faults , rev and first wii be selected wether ecu works or not but changes could be effected

Ok interesting I'll have a look at that later ive installed a Ecu extension so I'll have a look at that. If not it will be going to my mechanic Tommorow.

right have spoken to a couple of transmission places and they are both saying that its probaly a one way clutch broken and it needs a rebuild. both companys want 1500+vat fitted. or 950+vat for a recon box and torque converter.

how hard is it to take the gearbox out of a td5?

also cant beleive it needs a new box after 78,000 its a joke.

its usualy the one in clutch pack c,not to difficult to do ,probably was on its way out but change of oil bought it on suddenly as oil has a very high detergent effect,could give you instruction if wanted , i would be surprised if oil was clean that you had other faults