Nissan Maxima QX auto transmission
Pete Zahut
note this is a UK car, not american, in case it makes a difference) that is
currently experiencing cooling problems. The garage found the radiator to be
blocked and have a new rad on order.
At the bottom of the rad, and integral to it, is an oil cooler pipe for the
automatic transmission. When the mechanic disconnected the pipes to lift out
the rad he expected a certain amount of oil to come out but they were dry -
and I do mean bone dry. No oil has been anywhere near those pipes for a long
time, he reckoned. He said that he's come across situations where the oil
cooler pipe in the rad has been leaking so the pipes from the auto box have
just been joined together effectively bypassing the cooler pipe, but that
wasn't the case here. The pipe in the rad has not been blocked in any way as
he could/can blow air through it (and no oil came out then either).
So to my question:
Is there some sort of valve within the automatic transmission that only
opens when the fluid gets hot enough to need cooling down, and in this case
it's just never been hot enough to need diverting to the cooler, or should
there be a permanent flow of fluid from the gearbox to the cooler and back
again?
I should say that I've had the car for two years, it drives like a dream and
I've never noticed a problem with the auto box at all, apart from over the
last 6 months I've noticed downshifts becoming _slightly_ jerkier and when
going from neutral to drive there's a _slightly_ harsher jerk than there
used to be, but these really are very small changes from normal. ATF fluid
level is normal and no colour change.
This really would not have come to light if it had not been necessary to
remove the radiator but, now that it has, is it a problem?
TIA
E. Meyer
"Pete Zahut" <no...@all.com> wrote:
Is he saying the pipes are connected to the trans or just left open?
I guess there is a chance the inlet is blocked in the transmission. You'ld
have to drop the transmission pan to check it.
On some of the late '90s American Maximas & I30s that used the 3.0 (3.0 was
not used in 2002, they were all 3.5), the trans oil cooler lines ran to a
small loop of pipe that was mounted in front of the radiator and did not use
the lines in the radiator. Any chance you have that arrangement?
Pete Zahut
Thanks for your reply. The pipes were definitely connected to the
transmission and the oil cooler is definitely in the radiator rather than a
loop of pipe in front of it. The pipes in question are marked as number 6 in
this diagram http://i137.photobucket.com/albums/q235/darkdoo/radiator.jpg
You mention dropping the transmission pan. Is that easy enough to do or does
half the car have to be dismantled to get at it? :-)
Thanks again.
E. Meyer
"Pete Zahut" <no...@all.com> wrote:
The A/T pan is cleanly accessible on the US models. I assume the European
model will be similar. You might also check the forums at maxima.org & see
if anybody knows anything.
Pete Zahut
Thank you very much my friend, will do.