auto box question

[tonyALB1]

hi
as per my other topics
ive had my 300 tdi auto just over a month now
im very pleased with it as yet

my question here is about the transmission

i have read it should have a hp22 auto box wich has 4 forward gears

mine appears to have 5 or an overdrive after 4th

on gentle acceleration it will change up through the gears and get into 4th around 30mph by manually changing the lever into '3' it changes down into 3rd then back up when in 'd' with gentle pressure on accelerator its doing around 1600 revs at 30 mph it continues to accelerate gently upto 50mph at around 2100 revs and
changes up another gear and brings the revs down to around 1800

so it appears to have 5 gears or an overdrive in
or its just set up wrong

the gearbox appears to change up and down as it should though depending on accelerator position and speed so i think its set up correctly


any any ideas??

[andyb66]

[(Gray)]

I'm lead to believe that will be the torque converter locking up.
I understand that it acts as a solid link between pump and turbine in the fliud housing. The main effect is to reduce the engine revs at cruising speed.

I'm sure someone with a better way of explaining how it works will be along shortly.

I find it locks up on mine at around 50mph....so when I'm driving through the 50mph speed limit in the M1 roadworks, it's constantly locking and unlocking...

[tonyALB1]

kk thanx

im not a mechanic by any means but as i understand the torque converter is like a liquid automatic clutch

so i presume from what you have said it must be slightly slipping to allow the gears to change etc and then locks up (bringing the revs down) at 50 mph

am i right??

[blanche_90]

wow dennis!!
i have to say this, you really appear to know your stuff.
love reading your posts on loads of things, but espesially with autos.

[tonyALB1]

i agree
very detailed answer

i can picture the graphs you describe showing output power

thanx for the reply

tony b

[bigbadtonka]

if you go buy topgear it was cadillac......

[tonyALB1]

hi
im going off the original subject quite a bit

but while googleing for an answer to dennis's question i found this

http://www.expeditionlandrover.info/gearboxSwap.htm

it goes on about other gearboxes for landrovers im sure it will be an interesting read for some1 on here

ps still off the subject a little i can remember as a child my dad changed a colum change vertical up and down shift to a now conventional h plan gear box in a vauxhall 101

[automatic]

its really slow taking off and wont rev to give the power as if in a manual you might slip the clutch to get the rev up ...it used to rev high to get taking off
and when cruising will change down at slight hills and loose sppeed until on the flat again....the engine revs fine in neutral etc. the gear box clunks when going into drive and then back to reverse also..any help its an old girl 1994 300tdi

[tonyALB1]

hello agen

seen as we seem to have a very knowledgeable person\s on here ill ask another question then.

i like this idea of torque converter then, cos when under 50 mph you can take foot off accelerator ie when goin down hill to coast a little will save a little on juice and engine wear as revs come down to just over tick over speed.
just the same as it locks up at 50 mph to bring revs down agen

my question is, is there an easy way of changing that lockup speed to say 46 or 47 mph then in a 50 mph zone you can keep to 50 mph + - a few mph without it coming out of the 'lockup' stage
i recon it might just be 1 screw somewhere that just neeeds a quater of a turn or something?????
ps mine seems to be exactly 50 mph on the speedo

[Ray_Jnr]

wouldnt life be great if changing the lockup speed was that simple, sadly its not.

Replace your auto box for a 3.5 RRC box IIRC they lockup at 45mph or get a quote from Ashcrofts to convert your box

[scut44]

I would read FAQ's in
www.ashcroft-transmissions.co.uk

Then i would leave well alone.
A quarter turn etc can make a big difference to your gearbox,
in as far as changing up etc.
This is the 'kick down cable' adjustment.
Quicker up change,slower down, you may well know when its not right..
(it can be wrongly set now, but then again it may be perfectly adjusted.)

Yours may require a little adjustment, but please dont do it by trial and error.
Have it done by someone in the know.

"whats the worst that can happen?"
Hundred and hundreds of pounds worth!

There are further and more involved changes, but these involve valve blocks,internals etc.

Diesel & petrol/v8 boxes are different with different changing properties.
V8's have bigger torque converters among other differences.

If you have a good working box, i would leave well alone and count your blessings.
Best not to meddle.
george

[automatic]

i dont think its the gearbox....i started it today and it took 5 or 6 seconds to build up the rev from when i put my foot on the excell pedal....it takes off like a honda 50 under the bonnet...no smoke new lift pump fitted the intercooler pipe going to the turbo swells when it eventually revs out...any help appreciated

[tonyALB1]

yeh my auto seems to work just fine
i thought it might be a simple ajustment to ajust lockup speed if not ill leave well alone whilst its workin fine

ps checking auto fluid level

it says in the handbook you need to check it whan ambient temp is about 20 degrees
thats not gonna be till next summer
it seems like there is a litle too much in at mo i have selected 1 then p then 1 then p then turned engine off on level ground then checked but it was a cold night outside when i checked it am i doin it rite does it sound rite to be a little over the limit in these conditions

ps like i say all is workin fine so i may be intefeerin with sumthin that dont need to be messed with