AL4 converter query

dimistyle

dimistyle

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So I'm following up on a couple of AL4 box swaps plus just opening mine up and installing a new oil pump and filter since I need take the box out of the car why not give it a go :roflmao:, but parts at short notice will be the problem.

My current box has a converter part no. 2001 C6 as its code, this appears in both C5 I, and C5 II petrol and diesels as well as some Peugeot's of the same era.

I have also found another AL4 auto in a Xsara 1.6i Petrol (low kms) with the same stamping as mine but has a different converter according to

Citroën Service

so the question is are the converters interchangeable or do i need to find the exact match if swapping boxes?

And before you ask No I'm not going to do a full AL4 rebuild just need to get this car moving as the neighbours are hounding me daily. :crazy:

some help please Froggys
 
Dimi,
No one else has answered so my two cents worth.

The converter is matched to the engine characteristics. so various different ones are common for the same transmission fitted to various models. So yes another converter will fit ok if it is for a AL4.
If you get another transmission then fit your original converter to it if the new one is different. Note the converter must be fitted to engage several items as it is fitted into the transmission in three steps, so ensure it is fully fitted in place and secured before you start lifting and fitting the heavy ackward transmission. There would be a distance to measure from the front face for a check. Rotate the converter so it engages the two splines and the pump drive (tangs or flats). Avoid damaging the seal also.:)
Jaahn
 
Well I have decided to do the complete AL4 replacement with a hopefully known good unit (thanks garethb) so I now have new oil seals for the drive shaft (left and right) and end seal (oil pump end) thanks to Wayne at Cullen and Sons (Nambour). Have all the cables disconnected, and now the neighbour let me know I can use his V8 rebuild workshop next Sunday :cheers: yeah a hoist and engine hoist rather than trolley jacks. So another tow truck to Maroochydore and should only take 1/2 day to swap over.
I will use my valve block which has the new solenoids, my torque converter (hoping this is not the route of the problems) and hopefully this should get me on the road.

If anyone is interested in helping out or popping in to check progress (Ken W , shanadoo) let me know and I will get the address to you.

Otherwise any other helpful advise would be appreciated, what is the best method to remove the existing oils seals, and the best way to disconnect the trans cooler without loosing too much fluid as I'm not sure if it has Citroen coolant or aftermarket so will only top up with distilled water until I can do a full flush and refill.:crazy:
 
I'd always thought the petrol and HDi gearboxes used a different converter and C&P ratio. Anyway, you must fit the converter to the gearbox and then offer it up as already suggested. There is some data given in Citroen Service and also the Mechanic's handbook. An early version of the latter shows RHZ HDi with an AL4 marked 20TP43 and C&P 25x68 and 2.0 petrol C5 as 20TP42 with 23x73. You might check that.
 
David S the replacement box will be a 20TP93, and I will install my original converter, the current box is a 20TP22 (which looks like was fitted to the Xantia) this car has had a rebuilt AB box back in 2008, so I guess an older version was installed. I don't think there should be any issues with compatibility. get it moving, 1st then off for a RWC.
 
dimistyle said:
David S the replacement box will be a 20TP93, and I will install my original converter, the current box is a 20TP22 (which looks like was fitted to the Xantia) this car has had a rebuilt AB box back in 2008, so I guess an older version was installed. I don't think there should be any issues with compatibility. get it moving, 1st then off for a RWC.
Click to expand...

Wish you luck matey!
 
David S said:
I'd always thought the petrol and HDi gearboxes used a different converter and C&P ratio. Anyway, you must fit the converter to the gearbox and then offer it up as already suggested. There is some data given in Citroen Service and also the Mechanic's handbook. An early version of the latter shows RHZ HDi with an AL4 marked 20TP43 and C&P 25x68 and 2.0 petrol C5 as 20TP42 with 23x73. You might check that.
Click to expand...


That's what I thought also. Hdi hatch = high gearing, petrol lower. Break Hdi lower again or could be the same as hatch petrol, then petrol powered break lower still. Plus it seems some tire profile swapping took place to alter the final gearing yet again.
I have early break 2ltr petrol box No 20TSO3 C/P ratio 23x73. My 2004 C5 Hdi had a 20TP948W with 25x68, a replacement box at 60thou with a dreaded BA exchange unit, so can't say if it's original gearing but should have been. I need a nap.
 
David S said:
I'd always thought the petrol and HDi gearboxes used a different converter and C&P ratio. Anyway, you must fit the converter to the gearbox and then offer it up as already suggested. There is some data given in Citroen Service and also the Mechanic's handbook. An early version of the latter shows RHZ HDi with an AL4 marked 20TP43 and C&P 25x68 and 2.0 petrol C5 as 20TP42 with 23x73. You might check that.
Click to expand...


That's what I thought also. Hdi hatch = high gearing, petrol lower. Break Hdi lower again or could be the same as hatch petrol, then petrol powered break lower still. Plus it seems some tire profile swapping took place to alter the final gearing yet again.
I have early break 2ltr petrol box No 20TSO3 C/P ratio 23x73. My 2004 C5 Hdi had a 20TP948W with 25x68, a replacement box at 60thou with a dreaded BA exchange unit, so can't say if it's original gearing but should have been. I need a nap.
 
Oh well that's my only option at the moment the proof will be in the pudding! I just woke up from a big nap dam influenza that I picked up from the kids. May not have any strength to do the swap on Sunday but workshop is booked so I better rest up. Thanks for the details

Sent from my GT-I9195T using aussiefrogs mobile app
 
I'd think the potential for problems when altering the C&P will be where the vehicle speed (gearbox output speed) doesn't match what is expected for a given engine rpm and selected gear. It may conclude it has a slip fault and dump you into 3rd gear. If it's otherwise the same and you still plan to open it up, it may be possible to swap the C&P over.
 
Hi dimi :)
Good luck and we hope you are feeling up to it.
If you put it in and find there is a problem due to an incorrect ratio that could be worked around. But lets leave it till it becomes a problem if ever.

If you do not take the top off the coolant bottle it will not run out much and you can tie the hoses up high to stop the leaking as you change over.
Jaahn
 
Ok job called for for today due to the lack of tow trucks in the area, as they are all at Powercruise so this gives me time to re-coupe.
I checked they differences between the differential C&P and looks like the revs on the diesel unit will be (3.17) 2800 at 100kmh will now change to (2.75) 2400 at 100kmh, so to bring it back in line I could if I have to change the tyre profile to 195/45 x 15 or similar. I'm hoping as I spend 80% of the driving life on the highway at 100-110kmh it should be OK. well thats the theory. thanks for the advise so far..
 
Changing the tyre size and even setting a different size via Lexia (i.e. maybe telling the car a porky) won't change the fact that it would have an expectation of the gearbox output speed for a given gear and engine speed. That's why I think you need to be careful about changing the C&P by fitting a gearbox from a different model. I don't know if you can specify the C&P in the BSI configuration of the car. If you can, that might solve the issue, but if you can't, which is likely, you may run into trouble.

You should see the C&P ratio given in Citroen Service when it lists the gearboxes used in the model by engine. With the VIN, you'd get just one, without, it should give you a selection of pages to view for different models within the range. The Mechanics Handbook was issued by Citroen at various times and contains a pile of useful information about the range. You can still find and download it in English for the older C5-era cars, but not for some later models. Try this page:
CARNETS DE POCHE which is the main English index page.
You will want this file for 2004 C5:
http://service.citroen.com/dtt/CDP/donnees/en_US/en_us_t2_2004.zip
Hope that assists.
 
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