Transmission slips...not at first

Which engine do you have in your car the size?Also do you any codes in you computer?

V6 3800 Series II. Check engine light is not on. no Diagnostic test

Usually when the transmission slips it will set a code in the computer.So they told you since the check engine light wasnt on that they wouldnt check forcodes?Will they let you rent a scanner from auto zone to check for codes yourself?Thetwo main reasons transmissions slip is too low of line pressure inside the transmission or a leaking clutch pack piston inside the transmission.

I got a code P1811

Ok now were getting somewhere that is saying its taking longer to shift then .65 seconds and the computer cannot shorten that time so it sets that code.If you keep driving it like that for too long then it will destroy the transmission.I would say its most likely you have a bad pressure control solenoid in the valve body in the transmission.But you would have to do some tests like a line pressure and control test on the transmission.Also need a scan tool with the correct sofware to do that super expensive and also need a transmission pressure gauge as well.You would also use that scan tool to look at the shift times between 1st to 2nd etc to follow the different steps on the trouble tree.Its best to take it in to a good transmission shop its not going to be a do it yourselfer on the diagnose part anyways the tools are expensive.

Could it also deal with relays, or low fluid?

Would it be cheaper just to replace it?

Its not a relay its most likely a bad pressure control solenoind but without proper testing that would be a guess.As far as the fluid level you can check that i doubt its that though.As far as a replace verus a repair if they found a good amount of metal in your transmission pan then i would say yes.If itd just the solenoid then i would say no.

how much would this cost me for the tests (ballpark figure)?

I would say 2hrs labor times shop labor rate i dont that it varies from city state etc.

how mush would it cost for you?

Again it all depends on what shop etc i would say 80-100 per shop labor hr so 160-200 for 2hrs labor.

ok. Thanks you.

Your welcome keep me posted on what they find.

I have one more question. I check my fluids yesterday. It was really low. I put some in there. Today (12 hours later) I drove it. It ran with no slips, or hard shifting. The only thing was that the RPM's whent higher than normal once on the way to work. Should I still get the test done or drive it for the weekend, and see how it does?

How low was it?Was there any visable leaks?if its shifting good now i would have the code p1811 cleared and see how it shifts and if the code comes back and go from there.

I will check for leaks, and reset the code, and tell you what happens.

it was below the first whole.

How many quarts did you add?

about 1 quart

Thats not a whole lot but if it was that low it has to have a leak some where or the last time the fluid got changed it was never fluid up with the correct amount of fluid.

I will check for leaks.

ok keep me posted.

I have no leaks. Just to check to see if I was right. What type of transmission fluid goes in to a 99' Pontiac Grand Prix GT

It takes dextron VI.

that was I thought!

Anytime.

Is my car OBD2 compatible?

Yes your car is obd2 all the cars 1996 and up are obd2 systems.

How and where do I connect an OBDLink scan Tool?

Should be on the drivers side on the edge of the bottom of the dash.

I'll check. Thanks

Your welcome anytime.