2004 Volvo S80 slips

I have a 2004 Volvo S80 which slips in first gear when it gets warm. When it slips, I have to shut the car off and turn on again, then it drives fine after that. Does Volvo have a sensor which detects that the transmission is low on fluid which causes it to do that? There have been times when I start the car, that it doesn’t want to go in to gear either.

If you think the fluid level is low, and it acts like it is low, why not have it checked?

I have not heard of a fluid level sensor in a transmission. Temp and pressure, sure.

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Yes, the car has a sensor in it that should detect low fluids.

Generally, it’s called the Driver.

Check your manual for how to use the various dipsticks under the hood. If there isn’t a transmission fluid dipstick, that the car to a mechanic who can check it.


Wow, what a bunch of you know what! If you know anything about the car, you would know its a sealed tranny. There is a dip stick way down in the engine bay that is not accessible. That is the reason for the question!

Note the last part of my response, to take it to a mechanic so they can check it.

Regardless of the fluid level, it sounds like you have an issue with your transmission.

Good luck.

Lack of a dipstick does not equal sealed. I suspect this transmission has not had fluid changes performed at the normal interval of 30-50,000 miles.


Maybe I should reword the question, does anyone know if the 2004 Volvo S80 has a sensor that will prevent the car from going in to drive or reverse if the transmission fluid is low.

The 2004 Volvo has a sealed tranny according to Volvo and there isnt anything in the manual about checking it. Supposedly according to Volvo, the fluid never needs relplaced. The car isnt mine but I have been looking to buy it at a real low price and it could be a real easy fix by just changing the fluid out and adding Lucas transmission fix

If you have not bought it yet run away, buy something else. An old car with a suspicious problem is not worth the risk. You are looking at potential big $$$$ repairs.


I would compare this to someone hanging around outside a VD clinic, trying to find a date for the evening.


If it was that simple to fix why has the seller not done so ? Because it is unlikely to help. Look for something else.


Agreed about running away from a used Volvo, especially one with a suspect transmission.

A friend of mine got a “great deal” on a used Volvo once. Turned out it was in the shop constantly for all sorts of issues…and every trip to the mechanic cost around $500 minimum.

There are plenty of other non-European used cars out there without suspect transmissions.


Just watched a video on changing fluid. Has yellow dipstick. Just like my rig. The dipstick is hard to find. Got 3.5 qts on drain. Not much vs total capacity. I might do it on my torrent I got in July. I have to loosen front motor mount to do it. Annoying.

If you believe it’s a “sealed tranny”, I have a bridge in Brooklyn I’d like to sell you for a bargain price.


If you read my messages you know its not. Its got a dipstick way down in there. Volvo calls it that!

This is exactly what happened to me with a used SAAB, I’ll never buy another one–too many sob stories. The car was excellent, when it was out of the shop.

I finally took the car for a drive, I didn’t feel the transmission slipping. What happens on occasion is when you come to a stop, the car will not go in to drive or reverse unless you shut it off and back on. That points to a fluid level issue which is very difficult to even check. I negotiated a price of $800 for the car. The car is in very good shape with no accident damage or even scratches. The tires are newer and the brakes pads were just replaced on the front. I thinks it worth a gamble. If it does turn out to be a bad tranny, I could easily sell the car for a $1000

Not necessarily, the fluid level increases by about one quart from cold to hot so low fluid level problems tend to go away after warm up.

The disengagement issue might be caused by a solenoid failure or a major failure. Start by checking the fault codes in the transmission control module or just change the fluid and pray.

It seems that most people fear buying an old car that needs work, isn’t this what the car hobby is all about?

When I test drove the car, the engine was cold and at best warm when I finished. While checking it, I tried it in manual mode and didn’t work either. Besides some minor interior work and possible power steering pump, I consider it a weekend project car. I really don’t consider $800 a lot of money for a car to tinker with.

A cheap project car. Is what it is. Maybe you can fix it?
Video shows short yellow fill plug. Let’s see if it exists. Prove YouTube wrong.