Auto gearbox problem?

[hertsbiker]

Being new to auto's, I was wondering what was causing this;-

Selected "D", arrive at lights. Floor it, excellent power, but then revs out without changing up. Part throttle works fine. Couldn't replicate it again without wheelspin, so backed off.

Is this a simple "top up fluid" job, or is it knackered? I'm beginning to have my doubts about this...

Carl

[campbell]

Hi Carl
What make and modle of machine are you driving??

Campbell

[big rumbly]

try topping up fluid first.
If not, it sounds like a torque convertor problem.

[hertsbiker]

it's a 6.2 litre V8 detroit diesel engine, running through a 3 speed 'box.

The truck is an 84 Chevy. I really need advice on this as I don't know if I can rely on it for day-to-day use?

Could this have been a "one off" due to being stored for a few months?

[mondeoman]

quote:
it's a 6.2 litre V8 detroit diesel engine, running through a 3 speed 'box.

The truck is an 84 Chevy. I really need advice on this as I don't know if I can rely on it for day-to-day use?

Could this have been a "one off" due to being stored for a few months?

Try pootling along in third, then floor it. See if it kicks down ok. Could just be a linkage problem, rather than hydraulic.

[hertsbiker]

quote:
Try pootling along in third, then floor it. See if it kicks down ok. Could just be a linkage problem, rather than hydraulic.

please explain what the linkage does? I'm totally out of my depth here! ta.

[hertsbiker]

oh, and the other thing, it makes quite a bang when going from D->R, R->D. I know they all do it a bit, but not sure if this is a bit excessive. Possibly it's the fact it is a 6.2 engine, possibly that it is 1984 technology??? or just plain worn out?

[mondeoman]

quote:
please explain what the linkage does? I'm totally out of my depth here! ta.

IIRC on older 3-speed autos there's a direct linkage from the throttle to the 'box - if this is out of adjustment then when you give it full throttle it won't necessarily allow it to kick-down (or perhaps change up?) I'm not an expert by any stretch, just stuff that I remember from the bad old days.

As for the clonk - that could just be play in the rear diff (crownwheel and pinion backlash).

[hertsbiker]

ahh, cheers lads. 1/2 pint of fluid has calmed it down loads..... bit more tomorrow.

[davidy]

Don't want to be alarmist, but I had a series of funny kickdown issues, high rev surges, etc on a Volvo Estate. The issue here was that the gearbox had its own oil cooler and this was built into the normal radiator, the metal between the two broke down putting water in the gearbox and transmission fluid in the cooling system. Result shagged gearbox and significant credit card flexing bill.

Might be worth checking if your gearbox has an oil cooler and where it is, if its seperate from the radiator then no worries, if its not, keep an eye out for murky coolant in the cooling system

davidy

PS if any of you out there have auto Volvos, I would recommend changing the radiator as a service item every five years or so, £200 for a radiator with built in oil cooler fitted is a lot cheaper than £2500 for a fitted gearbox, because many Volvo boxes are special runs for Volvo only and cannot be rebuilt cos Volvo keep all the parts and will only sell complete boxes.

[sjc]

Hertsbiker, if you don't solve the problem, I can highly recommend an Auto-trans specialist Hornchurch, Essex