Transmission Fluid Flow Rate through Radiator problem?

"Ron(Tx)" > wrote in message
...
>
> > wrote in message
> oups.com...
>> My new transmission is (still) overheating on long highway drives.
>>
>> Transmission shop tested the t-fluid flow rate through the radiator at
>> 1 quart every 30 seconds.
>> The transmission itself however will push times that amount, 3 quarts
>> every 30 seconds, all by itself and also through an aux t-cooler.
>>
>> My radiator is only 2 years old. When I first started having
>> transmission overheating I found the radiator was shot and had it
>> replaced and later put in a tran cooler too.
>>
>> So the questions is...
>> What should be the t-fluid flow rate through the radiator?
>> In other words... is my radiator restricting t-fluid flow rates below
>> spec?
>>
>> 1993 4Runner, V6 3L, Auto, 4x4, 170K
>>
>> Thx
>> Dave-in-Denver
>>
>
> 95 4Runner, V6 3L, Auto, 4x4. I had a trans overheating problem also.
> After a heated discussion with my dealerships service manager, where I
> told him that my trans was overfilled and I thought that was my problem,
> he called Toyota. The fix was to check and make sure the trans was not
> overfilled. It needs to be checked after idling for 15 minutes. If it's
> overfilled it will cause the clutches to slip and overheat. On my last
> service they had overfilled it. They changed the fluid and filled it to
> the correct level and the problem went away.
>


Ron,
He has confirmed that the fluid does not flow efficiently through the
radiator.

>
> Ron,
> He has confirmed that the fluid does not flow efficiently through the
> radiator.

Hi Jeff,
Yes... my radiator will only flow 1 quart in 30 seconds (a third of
what the tranny fluid pump wants to push) and that it did not improve
after spending the nigh on the flush/cleaner machine.

4Runner is still in shop... owner working on this himself on a hit/
miss basis rather than one of the his usual guys. So tomorrow he
expects to tell be result of the flow test through a NEW radiator.

Thx
Dave-in-Denver

>
> Hi Jeff,
> Yes... my radiator will only flow 1 quart in 30 seconds (a third of
> what the tranny fluid pump wants to push) and that it did not improve
> after spending the nigh on the flush/cleaner machine.
>
> 4Runner is still in shop... owner working on this himself on a hit/
> miss basis rather than one of the his usual guys. So tomorrow he
> expects to tell be result of the flow test through a NEW radiator.
>
> Thx
> Dave-in-Denver

Picked up 4Runner yesterday with new Radiator (and same aux cooler).
T-fluid Flow rate through the radiator was great... "over a gallon in
less than 45 seconds" according to the shop owner. (Wish he had done
an apples to apples time/volume test... but the flow was "so huge"
compared to the bad radiator the tranny shop knew the problem was
solved.

AND they did not overfill it... in fact the t-fluid levels are at the
mid mark on the dipstick... not the high mark.

I have a 6 hr drive in the mountains tomorrow with temps in 80's...
will be a good test.

Thx
Dave-in-Denver

> wrote in message
oups.com...
>
> Picked up 4Runner yesterday with new Radiator (and same aux cooler).
> T-fluid Flow rate through the radiator was great... "over a gallon in
> less than 45 seconds" according to the shop owner. (Wish he had done
> an apples to apples time/volume test... but the flow was "so huge"
> compared to the bad radiator the tranny shop knew the problem was
> solved.
>
> AND they did not overfill it... in fact the t-fluid levels are at the
> mid mark on the dipstick... not the high mark.
>
> I have a 6 hr drive in the mountains tomorrow with temps in 80's...
> will be a good test.
>
> Thx
> Dave-in-Denver
>
Thx for the feedback...
Ron

> Picked up 4Runner yesterday with new Radiator (and same aux cooler).
> T-fluid Flow rate through the radiator was great... "over a gallon in
> less than 45 seconds" according to the shop owner. (Wish he had done
> an apples to apples time/volume test... but the flow was "so huge"
> compared to the bad radiator the tranny shop knew the problem was
> solved.
>
> AND they did not overfill it... in fact the t-fluid levels are at the
> mid mark on the dipstick... not the high mark.
>
> I have a 6 hr drive in the mountains tomorrow with temps in 80's...
> will be a good test.
>
> Thx
> Dave-in-Denver

No OVERHEATING TRANNY!!!

Drove 300+ miles yesterday in the Colo mountains and not one blink
from the Tran Temp Light. So the radiator was in fact the the bad
guy.

Checked fluid level 6 times. Had everything from half an inch under
the low end of the "hot range" on the dipstick to half an inch over
the high end of the "hot range".
- The highest level was observed one block from the highway after a
hard fast mountain pull.
- The lowest level later observed was later in day on the return
trip home after power costing nearly an hour back down into Denver.

Thanks to everyone for there comments/suggestions!

Dave-in-Denver