speedometer/transmission

Help
Hello everyone, I am new to your forum as I have just purchased a 98 Windstar van with 3.8L engine.
My problem is that the speedometer is intermittenly working and when it is not working the trans is not shifting correctly. the speedometer says 0mph and sometimes when driving about 40? the trans will shift into OD for a few seconds, then do a abroupt downshift to 2nd I think. Then when you press the throttle the tach just revw up with no forward motion of the van. At a certain point as the van is slowing down the trans will catch and start going again. I have only had this happen when the speedometer is not working. I
If when it won't go I down shift into 2nd manually and then shirt back into drive it will start to go again.

I have looked at the trheads ti tne archives and I am thinking that the Vehicle speed sensor is the problem. I purchased one at the auto parts store as well as a Chilton manual and the manual dosen't say anything about the VSS. I am so mad!

Anyway my question is does anyone know where exactly the VSS is and how to change it? (ie: any special tricks)
Again I looked at the archive and I crawled around and under the van but I can tell where this part is.
Any help is greatly appreciated!!
Thanks Guy :uhoh:

I know this does not help, but my 98 Windstar is doing the EXACT same thing. We had the VSS replaced at a dealership and the codes cleared, less than 30 minutes the check engine soon light was back on again with the VSS code on again. If you have any help, please pass it on to me. We have been dealing with this situation for about 6 months with no help from the forum. PLEASE HELP!

Hi...I just went through this myself. I did a lot of research, and have instructions on installing the VSS and TRS. It is all too complicated to write. You may call me at my office (914-921-6900) 8-5 EST Mon-Fri and I will be happy to tell you what I know. Ask for Fred

Thanks, I will call you and thanks for your help.