td5 auto g/b, earlier selection??

my 99 td5 auto seems somewhat reluctant to change into top gear when cold, once warmed up it changes at around 55mph.
would a g/b oil change be a help (do they have a filter?)
any advice on getting into top before 55 ??

Are you sure that it's "top gear" it's not changing into, or, are you refering to the torque converter lock-up feature - which normally comes into operation at about 50-55mph?

this could be what i'm refering to, i'm not sure.
normaly at 55 the revs drop as an engine would when moving up a gear but in a morning it seems to take forever before this happens even if i cruise at 60 -65.
i was thinking the engine would not labour as much and it may improve mpg if i can get the revs to drop earlier...
hope this makes sense... thanks simon

Hi Simon, yes it sounds like you're talking about "lock-up"

How long does it take your car to warm up, and for the gearbox to behave normally?

From the viewpoint of economy, unfortunately you already know the best way to improve fuel consumption - back off that pedal.

Can't remember, have you done the De-EGRing thing yet? That's suppoesed ti improve fuel consumption a bit?

thebiglad said:

Are you sure that it's "top gear" it's not changing into, or, are you refering to the torque converter lock-up feature - which normally comes into operation at about 50-55mph?

Click to expand...

Easy to check - if you're doing about 50 and it hasn't "changed", shift the stick down to third. If it changes down then you're already in top. I think you'll find it's just the lockup. I've a suspicion it may be down to power available - cold engine, less power, later lockup. (CharlesY will now tell me that's b******s). Mine is locking up slightly earlier since I did the egr last week. And it's so much smoother and quieter all round!

EGR is blanked, from what your saying it sounds like "lock-up"
i pull straight out onto a A-road and travel around 3miles at around 60 before it selects/locks -up, always at the same point on the road (very consistent).
what exactley is the lock-up, how does this work??
thanks Si

simon j said:

my 99 td5 auto seems somewhat reluctant to change into top gear when cold, once warmed up it changes at around 55mph.
would a g/b oil change be a help (do they have a filter?)
any advice on getting into top before 55 ??

Click to expand...

This is normal, it goes into final gear/lock-down at 53MPH once the car has warmed up sufficiently. Mine goes when the temp needle hits half way. You'll have to just back off a bit until your car warms up!

Torque converter lock-up is a state an auto box goes into where all of the 'slip' coming from the torque converter is 'locked out' and you have direct-drive (ish) through the gears. Bit like "A gear and a half". Most efficient state for the box to be in for obvious reasons. Annoying when you're driving through a 50MPH zone though, and you're revving away, willing it to slip into lock-down!

You can read more about auto boxes here

James

thanks guys !!
sounds like the box is working fine and i will just have to get used to it..

Mine was much the same........ had the gearbox oil changed and it warms up faster and changes up quicker, and lock up occurs normally without undue delays.

Worth trying!

thanks Dan will give it a try. do you know what oil is used and how much is needed?.......

I couldn't tell you Simon, not being remotely mechanical, i always entrust all work to the guys who know!

Good luck.

from dry 9.7 L
atf dexron IID

according to the rave !!!

quite fiddly to fill though, may be just as well to leave it till the next service, and have the screen filter changed and the magnet cleaned at the same time.
mine felt totally different once this was done.

mat

Had my 'box oil and filters changed last week - apart from making a great difference to the running of the car (speed, noise, more free-revving with less lag), I can report that it will now lock-down at 53 MPH before it gets to half-way on the temp (as I had previously reported). Last night, after sitting on the drive for 2 days, it went into final gear lock-down whilst the temp was still only around quarter-hot.

Good stuff.

Just under ten litres of Dextron IID ATF ain't the cheapest though - But in my case I'm glad I did it and it is making a difference. The mechanic said that the oil was absolutely minging and black - completely wrecked. I'm just hoping now that my car's auto box was overheating because the oil was knackered, and NOT that the oil is knackered because the box was overheating...? If you know what I mean!!

James