D40 Auto 2009

[david m]

Hi all, have the transmission shudder yous describe when going into O/D, will keep pestering Nissan until fixed. Have a different problem if somebody can help. When going down hill at about 90k in O/D and you need to slow down to say 80k using the foot break the tranny drops down a gear or two and the motor sits on about 2800 rpm.
The only way to get it back into O/D is put your foot on the go pedal.
Nissan (Essendon Nissan) said this was an engine break and was normal? Had other auto's over the years and have never experienced this before. This is my first oil burner so i am not sure on this stuff is normal or the wool is being pulled over my eyes.

 

[KraftyPg]

Most diesels these days have engine brakes so Nissan are right. I'm not overly sure about your revs though mine never gets anywhere near 2800. I'm not a particular fan of the Nav's engine brake because I don't reckon is disengages as quickly as it should but as for it's operation I think it's quite good. The times I deliberately used to on the road the car has held steady at the speed I've wanted it to no matter how long the hill was, of course the longer the hills the more annoying the brake can be because you may have to disengage it and engage it several times over the distance but it works well in mine none the less.

 

[david m]

Thanks for the reply Krafty, I have had the car since new (may 2009) but i must have missed the page on engine breaks, how do you turn it on and off ?
Cheers

 

[KraftyPg]

I don't know that there is a page on engine brakes as such to be honest I don't even remember it being referred to in the book, but then I never read the book that well either so it's not suprising I don't know whats in there.

I don't know of any permanent way of turning it off like in most trucks but it will come on automagically when going down hill with either your foot off the accelerator or on the brake if the car senses that engine braking is required. The only way to stop it is to put your foot on the pedal again. Mine however is unlike any truck I've driven in trucks it only requires a slight amount of pressure on the peddle to disengage where as in my Nav it actually requires me to put my foot down and raise the revs by about 100rpm before it disengages. Thats the main reason i don't let it engage very often.

 

[the_bluester]

It is a feature of the auto rather than the diesel. I quite like it myself, saves a lot of braking down Mt Pretty Sally which we used to do five times a week. I drag a brake to get it to drop back into third down the hill and then at the bottom I just give the loud pedal a quick prod to get it to go back to the more normal mode. If you keep slowing down to a stop it just drives off like normal.

David, you will not have come across it before as it is a relatively new bit of programming in autos, our old Magna was supposed to do it but never did. It is still relatively uncommon. One of the more sensible things I have come across was test driving a new deisel Xtrail auto, when you stop at the lights it drops into neutral to save a little waer and tear and fuel, when you take your foot off the brakes it drops back into first pronto. it is back into gear before you would even have your foot onto the accelerator pedal.

 

[Old.Tony]

It's actually built into the TCM (Transmission Control Module) which is inside the gearbox. It takes data from the revolution sensor to determine vehicle speed, and the ECU which tells it when the brakes are being applied.

You may be able to disengage it by flicking the O/D button off and on again too. Seems everything automatic (braking and torque converter lockup) rely on the vehicle being allowed to go into top gear.

As for the feature - I like it. When we've got the caravan behind us it doesn't do a lot, but it assists the brakes on 8 wheels - that's not a bad thing.

 

[JPMC]

Old Tony's right if you flick it out of OD the engine brake will disengauge. (well it does in mine)

 

[david m]

Thanks everybody for the info, i can now sit down with a stubby in peace !
Great forum, it"s the only place i know of where you can be in your 50's an get called a "junior" Yoo Hoo !