Thread: Auto over heating issues

Not really an expert an trannies, but I would have thought that a failing pump or low pressure may also cause issues when the auto went to change gear as well. The solenoids wouldn't be getting the pressure they need to operate properly. I am happy to be corrected here mind you...

Cheers - Gav.

50-60k's in LOW - what gear?
If it was in 'D' then its maybe in 4th with the lockup clutch engaged (and therefore no converter slip/heat).

What are you using to measure the temp?

Steve

Gav - box works fine otherwise

Steve - oil temp gauge from repco fitting in line - has been there for 18 months - all this temp spiking is new

Yes D = 4th low range

The pattern is the same and regular so in same condition over 2 different weekend and 4 days of driving - last weekend 11 hr driving on one day - so pattern is established and recent - ie last few weeks.

So something systematic has changed.

Skiboy

Check that your trans cooler fins are clean, it may be blocked & not leting air flow throught it.

Originally Posted by Disco W.A

Check that your trans cooler fins are clean, it may be blocked & not leting air flow throught it.

This and also maybe coupled with low fluid level. Failing pump usually results in loss of clutch pack pressure but you would notice this with slipping and higher than normal revs in high range.
Low range reduces the load on the trannies but obviously will turn quicker.
Would check filter also and flush cooler lines also.

Cheers

Andrew

I reckon when its running cool the lockup clutch is engaged, but running hot at all other times. So essentially its unrelated to revs/airflow other than the lockup clutch is controlled by the output RPM.

As others have said - look for a general cooling issue.

Steve

have 300tdi with ZF in Deefer. Have had same problems at times. If auto cannot lock up will get hot ie off road use low range in higher gears, 3/4 rather than high range 1/2. I am not sure whether the auto "locks up" in other than 3/4 gear and therefore has to work harder.

I had cooler on front bumper which still got hot at slow speed but just installed cooler with radiator so that the fan is drawing air past cooler at low speed. Solved problem.

I am not sure about the locking up in 1/2?

Just a thought.

Brad

Thanks all let me clarify:

(1) Cooler is clean - condition unchanged - so not the issue
(2) Fluid was all changed out before the weekend and top quality synthetic ATF added - no change in the problem so not the old fluid or low fluid - in fact fluid levels were fine before and after.
(3) Cooler lines were blown out when oil changed

This phenomena was a recent change in operating temp so something has changed. No box operation issues in that gears all work fine.

Oil filter in auto - the auto place I went to said they need to remove the cross member and exhaust (this is a ZF from a Disco installed in a Rangie) to do an auto service.

Is this service - the filter and seal on the tranny bottom - doable by a novice with some mechanical expertise?

Thanks
Skiboy