I have a 98' F150 XL 2 wheel drive p/u ,4.2 v-6 ,problem is under lite acceleration it drops out of O/D , at highway speeds with cruise on every little hill or head wind pops it out of O/D , most times I run with O/D disabled (and my millage -which is about 15 MPG -improves some ).
My question , is there a product , or way to allow the transmission to stay in O/D under more load before it downshift's
like we did years back by unhooking the manual control rod from the carb to the trans.
It is very annoying to have it constantly downshifting , and running out of O/D, at highway speeds revs the motor.
Thx

 

Are you sure that you are not hearing the Torque Converter come out of lockup? It sounds like dropping down a gear when it unlocks. Mine does this sometimes as well.

 

Yes it is , I meant it that way thanks , but It seems to do it constantly, like I say a slight breeze, or just a vary slight incline ,the truck has enough power to overcome these obsticles with out droping down , I would like to be able to disable this
or at least alow it to develop more power before the t/c lockout drops out

thanks for the response

 

You haven't changed tire size to a larger tire have you?

 

have not changed tires , has the firestone wilderness 235/70R16
but they are getting thin

 

My truck tires are 1.6" taller than the factory tires and it tends to gear-hunt on small inclines.

 

(stating the obvious)

Taller tires on the drive wheels give the effect of less overall gear ratio. By less I mean higher gear, lower numerical. For example if you have a 3.55 ring and pinion, a taller tire could effectively give a 3.40 or something like that depending on the increased in diameter of stock.

My point is this - less gear means the engine has less leverage to turn the tires which in turn means the engine has to work a little harder on inclines and pulling loads.

Ok, I'm done now.

 

DD I agree with u 100% , but I do not have anything but stock 235/70R 16's on my truck ,(Firestone willderness H/T),I guess what I am asking is , is this normal on other readers truck's
to kick out of T/C lock at every little wind or incline ??
I am not used to this and it seems like it would be hard on the trans, sometimes when going into a head wind it will drop out and catch up then shift again and keep this cycle till i get frustrated and punch the O/D button . or untill the wind dies down or the incline is levels off.

 

I had a '98 XL 4.2 and never noticed what you are describing. The only things I changed in that truck were I installed a SuperChip and a B&M Electronic Shift Improver.

 

B-man tell me more about the B&M shift Improver ??

 

Superhero -
I have a 95 F150 flareside with 5.0 and 4r70w and I have never noticed what your talking about. It will downshift on steeper inclines but it is a definate downshift - it really pulls hard.

 

Doggie , am sorry for the confusion , my Old truck was a 5.0 and I loved it , and it did not do the down shift thing , Its my current truck with the 4.2 six that does , man keep the 5.0 they run forever , and they have enough power to handle the job PLUS they get better MPG !

 

I bet all you're dealing with is normal shift character for that motor tranny combo. The 4.2 is good motor. Don't let it's smaller size fool you. It just has to work a little more for the same effect.