Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Derek_in_Penzance on 30 July 2020, 18:13:39

Title: X25XE and X30XE auto gearbox differences pre and post chassis V1999999
Post by: Derek_in_Penzance on 30 July 2020, 18:13:39
Can anybody tell me whether X25XE and X30XE auto gearbox differences pre and post chassis V1999999 are important?

I have a pre-V1999999 auto gearbox for a 3.0 V6 to go in a later chassis number (a Y chassis number).
The Vauxhall electronic parts catalogue shows different part numbers but I can't see any chassis breaks for the internal components, just the control ECU. I assume that the change programming is just slightly different and that for all practical purposes there is no difference between pre and post V1999999 gearboxes for the 2.5 and 3.0 cars.

Any advice gratefully received! Thanks.
Title: Re: X25XE and X30XE auto gearbox differences pre and post chassis V1999999
Post by: Doctor Gollum on 30 July 2020, 18:49:16
Technically, the 2.5/2.6 uses an AR25 whilst the 3.0/3.2 use the AR35.

The AR35 is preferred as it's a higher torque rating. Physically they are interchangeable, and you would simply unplug and remove the existing box and throw the new one in.

That's about as uncomplicated as it can be :y
Title: Re: X25XE and X30XE auto gearbox differences pre and post chassis V1999999
Post by: Derek_in_Penzance on 31 July 2020, 09:04:33
Thanks for your reply, I may have sown confusion by throwing in the 2.5 box as well, what I was saying was that for the 3.0 gearbox with torque converter that part number is 96016629 up to chassis number V1999999.
Subsequently from chassis W1000001 , the 3.0 gearbox is 96018038
I don't know what difference triggered a new part number, often it is something very minor that is of no great consequence, other times it can be really important. I just want to make sure I can use the "early" 3.0 gearbox to replace the faulty 3.0 gearbox on the Y-reg car without any obvious incompatibility.

(For the 2.5 gearbox the part numbers are 96016628 to ch V1999999, then 96018037 from ch W1000001 onwards).

Many thanks for your help.
Title: Re: X25XE and X30XE auto gearbox differences pre and post chassis V1999999
Post by: biggriffin on 31 July 2020, 16:52:54
You've confused me with all that...

 Basically, Autoboxes used in omega V6 are fully interchangeable, just don't put Ar25 in a 3.0/3.2!!!! Ar25, is shite, Ar35 is way to go.

 Ar25 fitted in 2.5/2.6
 Ar35 fitted in 3.0/3.2... as said by DG
Title: Re: X25XE and X30XE auto gearbox differences pre and post chassis V1999999
Post by: VXL V6 on 31 July 2020, 20:13:54
There is an internal difference between the AR35 fitted to a 3.0 car compared to a 3.2, I can't remember exactly what it is but Serek knows. Completely interchangeable and plugs are identical (although the ECU is slightly different).
Title: Re: X25XE and X30XE auto gearbox differences pre and post chassis V1999999
Post by: LC0112G on 01 August 2020, 21:07:40
There are differences in the cable tie points for the wiring. I *think* this is to do with the fact the 3.2/2.6 has pre and post cat lambda filters, whereas the 2.5/3.0 only have pre-cat. Other than that I didn't notice any difference when fitting a 3.2 AR35 to my 3.0 earlier this year, and it seems to work Ok.
Title: Re: X25XE and X30XE auto gearbox differences pre and post chassis V1999999
Post by: Doctor Gollum on 01 August 2020, 21:11:08
The brackets screw on iirc, so easy enough to swap if it's an issue ;)
Title: Re: X25XE and X30XE auto gearbox differences pre and post chassis V1999999
Post by: Derek_in_Penzance on 02 August 2020, 10:20:58
Thank you all for the replies, very helpful. It shows the value of internet forums for car enthusiasts, there are always people willing to give good advice.