# Transmission Slipping



## GWFL (Apr 26, 2005)

The transmission on my 2001 LE with 82k on it slips once in awhile in cold weather. The vehicle has spent its life in the warm weather of FL with flat smooth roads and a few years ago on a few rare days the trans would slip if I stepped on it hard while still cold. These last two weeks have been cold for us down here and I've noticed it slipping more often when the engine is still cold.

Is this the begining of a more serious problem or is slippage more common then I thought during cold spells?

Is it a clutch problem or transmission? What cost might I be looking at depending on type of repair?

Gary


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## NALtech (Oct 30, 2009)

You may be able to get your transmission for free by a dealer's nissan rep. to goodwill a transmission. With 82K your 2K out of the warranty, he may be able to help. BUT that it if it is the trans. Is your fluid full, in good condidtion?


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## rogoman (Dec 16, 2004)

Sounds like you have a clutch problem. Make sure there's enough free play at the clutch pedal.


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## NALtech (Oct 30, 2009)

Auto or manual?


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## GWFL (Apr 26, 2005)

*Update*

Sorry. Forgot to say that it's an automatic. I checked the fluid level today and it's fine. Fluid was replaced about 10k ago. Weather is warming up now so I'll experiment with it again to see if it will slip when steped on.

I have a very good relationship with my dealer but without a more definitive problem I don't think they'll spring for a new trans.

I'm due for an oil change in about 2k so I'll bring up the problem when I'm up there (60 miles away).

Are there any adjustments possible on these trans?

Gary


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## NALtech (Oct 30, 2009)

Shift linkage is about the only adjustment possible.


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## Smith1000 (Dec 29, 2005)

I also wondered if there is any internal torque adjustment on these transmissions, if the pan is dropped. Sounds like there isn't though. Used to to be able to torque the low and reverse bands in some automatic transmissions to reduce slippage in low.


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## bbswift53 (Dec 21, 2009)

There is a service bulletin from late 2001 regarding this. The fix it to replace the transmission control module (TCM) and the solenoid pack. My GF's 2001 QX4 has had the same problem for years, but I only recently understood what she was talking about (she used to say that it had no "get up and go" sometimes, and "made noise under her feet"), and then I was able to duplicate it on a cold start.

I got the latest TCM for $80 delivered from a 2002 donor wreck ($600+ new), and it is only a 10 minute job to swap it out. Unfortunately, it made no difference in the 2-3 slip when cold (not very cold, just ~50F). The solenoid pack is $292 is you use the official Nissan one (courtesyparts.com), plus pan gasket and fluid and maybe filter while you are in there. I'm reluctant to use the Transtar part ($100), since even the Nissan one was wrong from the factory. So far, trying to go easy until warmed up, and put up with it, rather than spending ~$400 plus labor. Once warm, perfect.

The ATF pressure (controlled by one of those solenoids) is intentionally lowered at colder temperatures, to compensate for the thicker fluid, so that shifting is not too abrupt. Well, I'd say that they screwed up the compensation. In fact, my GF's was behaving okay at 32F last week, at which temperature the fluid really is getting a bit thick, but not so well at 55F. I'm going to fake out her TCM by putting a fixed resistor across the ATF temperature sensor (thermistor), so that it thinks the the fluid is warmer, and doesn't drop the pressure so much -- I'll let you know how that goes.


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## GWFL (Apr 26, 2005)

*Seems Normal*

In the normal warmer weather it seems to be doing fine. I'll just have to give it some more time and see what happens. I'll be at the dealer in a month so I'll ask them about it then.

Gary


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