Re: 2000 Grand Cherokee v8 transmission issue
Thinking about it more, it is important to know if it slips in reverse as well. This is because the fluid flow in D 1st to the L/R clutch is different then the fluid flow in reverse to the L/R clutch. In D, the L/R shift solenoid will supply the fluid for the L/R clutch, while in reverse, its the manual valve in the valve body which supplies the fluid. So if reverse works ok, but it slips in D 1st, the problem is most probably with the shift solenoid.
If the problem exists in D 1st and reverse, an internal leak could be the cause and the air test for the L/R clutch will be needed.