OK, I just purhcased a 1990 ranger with a 4.0 from a 1994 explorer. It has an automatic transmission that seems to have a big problrm. It will not shift into 2nd or any other gear besides first. The truck will only go about 40 mph because it it stuck in first. What could the problem be. I test drove it the other day and it was fine. Could it be too much or too little fluid? Any help is appreciated. Thanks

 

The first thing i would do is check the fluid level and see where it is sitting. Its quite ironic how people buy used vehicles then days later major problems occur. Thats why i only buy new now!

 

Yea check you fluid level and pay attention to whether the truck is warmed up or cold. It can affect shifting sometimes. Most likely you have larger problems with the transmission though, they are nothing but bad news.

 

How hard is it to pull a transmission out of this thing?

 

Is there a sensor in the transmission that detects low fluid?

 

Its really not that hard to pull the tranny as long as you have the proper tools and a little knowledge about cars. Also i highly doubt that there is a low fluid level sensor on that vehicle. In fact i have never heard of one on any vehicle. At least not any that i have owned.

 

what about if you put the truck into say anything other than Drive

 

A heck of a lot easier than a front wheel drive car. Welcome to the world of trucks- where darn near anything is doable with a decent set of tools and a haynes/chilton manual.

The simplified steps:
remove all wiring connectors and shift linkages
Unbolt driveshaft
Remove starter
Unbolt torque convertor from flywheel
remove 5 or so bolts holding tranny to engine
remove tranny crossmember
slide tranny back and down from truck.

 

Well I have some good news. It turned out to be that the vacume line for transmission modulator was not even plugged into the intake manifold. So after 12 hurs screwing around with the truck I found out it was a 2 second job. I have one more question. It does shift now but only when I let off the gas. Could this be the modulator itself needing to be replaced? Thanks

 

Make sure that vacuum line isn't damaged. Not enough vacuum will make the trans act funny.

 

I think I will replace the modulator and the line. The line appears to be a pre bent metal one. Where can I get this part?