Auto gearbox doesn't seem to like minus 12

[CHASTER]

Monday
Early morning start out, B----cold. Motor fired up OK but had to pile on the revs to get moving.
All seemed very sluggish in the transmission department, would't go into overdrive at any price.
4k revs and still only doing 55ish. Acceleration (usually meteoric) was rubbish.

Wife said " Stop fretting ; at least we're moving and we've only got twenty miles to go".

Heater OK ,all else working OK----decided to relax and listen to the radio.

Return journey ? 16.00hrs and still minus 12.
Everything hunkey dorey; Rip snorting acceleration back, gearbox leapt into o/d at 60 ish. No further probs since.

Just left wondering what that was all about:nenau ?
No doubt someone has the answer!

 

[lacroupade]

I'm slightly confused by what you say....OD "in/out" is electrically operated and not vulnerable to temp, so I assume what you mean is top gear (with overdrive engaged, i.e. yellow dash light OFF....its not quite the same thing as "changing into overdrive" because you are already "in it")? If so, its quite common on the auto for it to take a while to drop into top....usually you find if you put the pedal down a bit more and then back off a tad it will change up. Its surprising how even the tiniest uphill incline - almost unnoticeable to the driver - can also make a difference.

It does tend to do it more often from cold though, but if it carries on doing it there might be a problem brewing; I think its a mix of solenoid and sensors that does the business so some element can go faulty. How many miles has the truck done?

If its history is a bit vague and theres a chance that someone has exceeded the towing weight limits (they are much lower on the auto, something like 1750kgs versus 3000kgs from memory?) theres a greater chance of a fault developing........so lets hope its been mollycoddled LOL

 

[Timbo_1975]

Erm, I thought that the O/D was inhibited below a box temp of ~50deg C to promote faster warm up on these?

At -12 during warm up for 5-6miles some sluggishness is to be expected due to the very cold lubricants etc, but this may not explain your issues.

 

[lacroupade]

Erm, I thought that the O/D was inhibited below a box temp of ~50deg C to promote faster warm up on these?

At -12 during warm up for 5-6miles some sluggishness is to be expected due to the very cold lubricants etc, but this may not explain your issues.

you could well be right Timbo, but I thought OD was on at least 2nd and top, not just the latter? yet its only that last gasp into top thats the issue, was for me when it occurred anyway, but often in decent weather....anyone got an original auto users manual can check for us?

 

[kbekl]

mine does the same thing on a very cold morning

altho drive is normal the over drive wont engage till it is at a cirtain temp normally 3 miles from home


might be worth checking the condition of the atf fluid and see what that looks like and smells like

 

[CHASTER]

I'm slightly confused by what you say....OD "in/out" is electrically operated and not vulnerable to temp, so I assume what you mean is top gear (with overdrive engaged, i.e. yellow dash light OFF....its not quite the same thing as "changing into overdrive" because you are already "in it")? If so, its quite common on the auto for it to take a while to drop into top....usually you find if you put the pedal down a bit more and then back off a tad it will change up. Its surprising how even the tiniest uphill incline - almost unnoticeable to the driver - can also make a difference.

It does tend to do it more often from cold though, but if it carries on doing it there might be a problem brewing; I think its a mix of solenoid and sensors that does the business so some element can go faulty. How many miles has the truck done?

If its history is a bit vague and theres a chance that someone has exceeded the towing weight limits (they are much lower on the auto, something like 1750kgs versus 3000kgs from memory?) theres a greater chance of a fault developing........so lets hope its been mollycoddled LOL

Sorry about confusing description. I did mean with overdrive button in and yellow dash light out.
Mileage is now 72k. Glad to say that, since ambient temp has risen, all is working well.
Don't know exact history of usage but auto box oil does not look cooked.

Thanks for your interest and reminding me about auto towing weights Rick. Easy to forget :doh

 

[Timbo_1975]

Suggest you change and flush autobox fluid as soon as you can. Have sump off and replace the cotton filter too.

Tim.