'99 Maxima transmission

My 1999 Maxima with 94K miles slips between 1st and 2nd. The Nissan folks say it might be a transmission valve that is sticking, and that if they flush the transmission fluid, it might make the situation worse and require the transmission to be replaced. However they also say that given my limited driving needs, I am better off just leaving it as is till it no longer works. Does anyone have any experience with a similar situation? Should I take the chance and get the transmission fluid flushed or take a chance and drive the car as is for as long as I can?

Flushing will not likely solve the sticking valve; it might make it worse. If you want it fixed properly, take it to a good independent transmission shop. They will drop the pan, check for debris, change the filter and tell you what the real problem is. Then you can decide whether to spend the money.

How often has the transmission been serviced? When was the last time the fluid and filter were changed?

This is not high mileage car, and Nissan transmissions will go twice that distance with proper maintenance.

I think it was done at 60K - since I know so little about cars I pretty much follow what the service department tells me to do. I don’t drive the car much so I reckon it was a few years ago that they did this. I was supposed to get it done at 90K which is about now.

Is it possible to diagnose this correctly without damaging the transmission? From what the service guys told me, I am assuming this isn’t possible

Can you describe what you mean by “slips between 1st and 2nd.” Slipping actually means that car leaves one gear, but then there is a delay in power to the wheels before engaging the next gear. What that happens, the car will leave 1st - then it will rev up really high and feel like it isn’t going anywhere at all - then 2nd will finally engage, the rpms go down and you feel like it is going again.

There are all sorts of other things that people use the word “slip” for. So, for example, staying in first gear too long without shifting to second isn’t slipping.

The thing is that these 2 kinds of problems are normally about different aspects of transmission function.

Did they actually run the transmission through any diagnostics? Did they say anything about “error codes” or “line pressures” or anything like that?

So your definition of slipping is what I am talking about. Re. diagnostics, no they didn’t say anything about error codes. They did run it thru a bunch of diagnostics but nothing apparently showed up. I suspect their diagnosis is based on what they think it might be since nothing else is showing up. I did have a check engine light a few weeks ago and they replaced a speed sensor at the time. This slipping was happening prior to the check engine light coming on.

I checked my maintenance logs. They flushed the transmission at 60K but there is no mention of replacing the filter. I imagine they’d have charged me for it and since they didn’t list it, I am assuming they didn’t change the filter.

Taking it to a transmission shop for a pan/filter service and more enlightening diagnostic would be a good idea. Figure $100-200 or so if you do.

Does it always slip between 1-2 or only sometimes? Is it mostly associated with either very heavy or very light throttle - or anything like that? Or it just does it no matter what?

Either way, the more you let the engine rev between 1-2 the less time there will be between now and the inevitable death of the 2nd gear clutch. So you might play around with what you do with the gas pedal when it shifts to figure out how to minimize the slipping.

In terms of slipping - it slips sporadically. I’ve noticed if I accelerate gently it is less antsy so that’s what I’ve been doing to minimize the slips. Sometimes you can barely tell it has done so. I think I will take your suggestion re. the pan/filter service. Thank you so much!

Gentle acceleration will minimize the clutch deterioration if it does slip - the worst thing is the high revs while it is slipping.

However, a harder acceleration will also increase the fluid pressure that is creating the shift and might keep it from slipping at all. If it actually jolts into a gear a little bit that is actually much better for the transmission than letting it slip. Within reason anyway - if you really jolt it hard that’s not so good. But a good firm - even hard shift actually minimizes the wear and will give you the most of whatever miles the tranny has left.

Thanks for the pointers. I’ll let you know what the trans shop diagnoses this as… I may need more guidance once I have that result!

Un-fortuneitly someone used the easy way, and not the right way to service the transmission. Easy for them. The better way is to drain it, remove the pan and clean it and the filter and put it back together. Flushing is easier.

I am not suggesting that it caused a problem. I am only suggesting that you should have the fluid changed, not flushed in the future.

Hang in there a little longer and maybe Transman may show up and he is THE man.