Hello All,

This is my first post on this site. I have an 1998 F150 that I want to tow four wheels down. The manual states that i need to cap off one side of the front axle vacuum motor. Can someone tell me how to do this? I would also like to know why. The manual also states that the max speed is 55MPH. I was told that ford only put that in for legal reasons and going over 55MPH will not hurt the truck. Can anybody give me info or opinions on this? I normaly drive at 65MPH

Thanks for the help

Les

 

Find the vacuum line running to your front axle, and unplug it Also, make sure you disconnect the rear driveshaft.

 

Thanks Zaairman,

I'm not sure what you mean by disconnect rear driveshaft. The manual tells me to just put the transfer case in neutral. Do i need to cap off vacuum line after I unplug it?

Les

 

If you have the manual shift transfer case, then you just put that in Neutral. If you have the electric Shift On The Fly (ESOF), then you've gotta disconnect the rear driveshaft.

 

Thank you Zaairman,

I do have the manual transfer case. I'm clear on the shifting it into neutral. I'm still not clear on should I plug the vacuum line after I disconnect it or just leave it unpluged? It looks like two lines going to the motor/axle so how do I know which one to unplug? It's almost dark here so i could be wrong on the two lines. Is there a way I can comfirm that the front axle is in the position it needs to be for towing?

Zaairman, I know I'm asking a lot of questions & I thank you again for you help

Les

 

Yes, there is one line going to each hub, but if its like my Superduty then there is a T connection in between the vacuum pump and the hubs. I'd just unhook the line straight from the vacuum pump.

 

ok, I got it now thank you. It sounds easy enough.

Thank you

Les

 

His is gas, so no vacuum pump. The easiest place to disconnect them would be on the firewall @ the solenoids.



BOTTOM VIEW

 

He said vacuum motor, so I just assumed that since I've got it, well, :o Thanks.

 

Ford calls a plain old diaphragm a "motor" ........ why not call a diaphragm a diaphragm ??????? I don't know........




At least they don't call the engine a DYNAMO ! !

 

Thanks for the pictures & Info. does it matter what line I unhook at the firewall? It looks like 4 vacuum lines in the picture

Les

 

The lines that are cut off are the vacuum supply lines. Mine are all faded out but there is a pink and a blue line. The pink disengages the diff lock and the blue engages it. I guess I would plug the pink one or both to have everything covered.
I see the towing instructions in the manual but I can't figure out why they would want the vacuum lines plugged.

 

Thanks for the info, This site has been a huge help so far


Les

 

I asked the question are several sites as to why the Vacuum lines need to be pluged and no one has had an awnser. I will go ahead and plug the line , but I sure would like to know why it has to be done in the first place.

 

I'd say its just to keep the chit from getting down in the line...