F40 Gearbox warning!

[diesel dog]

I don't wish to be alarmist,but it has come to my attention that owners of cars fitted with the F40 gearbox mated to the V6 diesel engine may be putting unnecessary stress on their gearbox.The F40 gearbox is rated at 295 lb/ft and not 400 lb/ft as some of us have been led to believe.So if you've remapped or boxed your V6 CDTI..BEWARE!

http://www.gminsidenews.com/index.php?page=trans_guide

[Duncan]

Yep, that's what I was trying to tell Nutron not too long ago. The same gearbox in our cars - 2.0T (close ratio), 1.9/3.0 (wide ratio) - is rated the same at 400Nm. States it quite clearly in TIS. It's not just 3.0 owners, it's also 1.9 owners who're running tuning boxes/remaps (or both! lol) and are producing torque above those figures that are in danger of severely shortening the gearboxes life.

[diesel dog]

When SAAB fitted the V6 diesel to their 95 back in 2001 the F40 wasn't available,so they had to fit the F35 (350NM or 258 lb/ft torque),this required the engine to be detuned to suit that gearbox and at the time there was no auto box available to cope with the torque,so the V6 diesel 95 was severely compromised sales-wise and it bombed!

[diesel dog]

I'm not sure which auto boxes are used on the V6/1.9,but in particular I feel that the 5 speed unit is probably definitely not up to the job when the engine is remapped/boxed.

[wardy]

Which cars have the F40 box? Mine is a manual 2005 V6.

I had a tunning box on it for a while, glad I took it off now!

[Duncan]

Which cars have the F40 box? Mine is a manual 2005 V6.

The same gearbox in our cars - 2.0T (close ratio), 1.9/3.0 (wide ratio).......

So yes, in yours as well.

[diesel dog]

Basically any six-speed manual I think.

[nutron]

Some 3ltr cdti's have made over 420lbft (569NM [400NM + 42%]) and the boxes are still in one piece. I don't believe they are rated to 400NM, the site you linked to has many factual errors on it. As for top speeds, I expect to see 155+ in Germany but I doubt it will make it to 5000rpm as the power/torque drops fast after 4900.

If VX changed the software and that raised the power, have you told insurance company? Even if VX did it, you wouldn't be insured if you didn't tell them.

[diesel dog]

Some 3ltr cdti's have made over 420lbft (569NM [400NM + 42%]) and the boxes are still in one piece. I don't believe they are rated to 400NM, the site you linked to has many factual errors on it. As for top speeds, I expect to see 155+ in Germany but I doubt it will make it to 5000rpm as the power/torque drops fast after 4900.

The fact that boxes are still in one piece is not really the point is it!

It isn't merely coincidence that the F35 is rated at 350NM and 258 lb/ft of torque and the F40 is rated at 400NM and 295 lb/ft of torque,there are other examples of that coding in the GM range.It is also no coincidence that Vauxhall only uprated the V6 to 295 ft/lb of torque when other manufacturers were already pushing past the 220 bhp and 350 lb/ft torque mark.The site does have some errors on it but it also makes sense in a lot of things it says.I believe that TIS states that the F40 is rated at 400NM.

If VX changed the software and that raised the power, have you told insurance company? Even if VX did it, you wouldn't be insured if you didn't tell them.

I'm not sure what the exact bhp of my engine is.I did mention this to my insurance company and they said that if it was a factory mod and was within certain guidelines then it would have no effect on my premium.

[Duncan]

I believe that TIS states that the F40 is rated at 400NM.

It certainly does, as I've mentioned to Nutron before - but he seems to think that's also wrong!!