1997 Ford F150 4x4 shudder?

Messages
1,754
Location
north carolina
I hear the word shudder but i guess i am not exactly sure what that means as far as tranny shuddering.. however its my dad's truck and when he takes off from a stop you feel a shudder like feeling. i dont think it does it as the tranny shifts at higher speeds. just take off.. to me this sounds more like a u joint and not the tranny. the truck has almost a 100k miles. any ideas?
 
Messages
14,776
Location
Illinois
Most likely you need to change the tranny fluid. While you are at it, drain the torque converter. Notice the rubber plug on the bottom of the bell housing. Pry it off and rotate the engine until you see the drain plug for the converter. Bad tranny fluid is the most common reason for tranny shudder.
 
Messages
625
Location
Georgia
Could be the u joints need to be replaced, or you may need a tranny flush. A good friend of mine experienced the same thing, but only at high speeds. The flush (BG products) cleared up the problem. Same thing for myself on a Plymouth Grand Voyager. Again, this was shutter at high speeds on both vehicles, which leads me to believe it's a u joint problem or trans mount has loosened.
 

mikeg5

Thread starter
Messages
1,754
Location
north carolina
yeah you only notice this at take off.. he will have the tranny serviced as well. we are going to do multiple drain and fills. probably use valvolin maxlife since its approved for MERCON.. as for the u joints how do you check them??
 
Messages
2,439
Location
snowblind in TX
If it is a single shudder or thunk from a takeoff, the splines on the driveshaft splines are binding. FoMoCo has a special teflon grease to fix the problem.
 

mikeg5

Thread starter
Messages
1,754
Location
north carolina
 Originally Posted By: punisher
If it is a single shudder or thunk from a takeoff, the splines on the driveshaft splines are binding. FoMoCo has a special teflon grease to fix the problem.
kind of yeah. you can only feel it at take off and thats it. isnt the shaft and all on that ford all sealed?? i dont think there are any grease fitting under that truck. keep in mind i have not been under that truck in a few years. my dad rarely does anything to it other than change the oil.
 
Messages
2,439
Location
snowblind in TX
 Originally Posted By: mikeg5
kind of yeah. you can only feel it at take off and thats it. isnt the shaft and all on that ford all sealed?? i dont think there are any grease fitting under that truck. keep in mind i have not been under that truck in a few years. my dad rarely does anything to it other than change the oil.
I'll stand by my previous post.
 

mikeg5

Thread starter
Messages
1,754
Location
north carolina
 Originally Posted By: punisher
 Originally Posted By: mikeg5
kind of yeah. you can only feel it at take off and thats it. isnt the shaft and all on that ford all sealed?? i dont think there are any grease fitting under that truck. keep in mind i have not been under that truck in a few years. my dad rarely does anything to it other than change the oil.
I'll stand by my previous post.
can you expand on that please? i do not know much about the f150 after speaking with a ford tech he said ujoint or clutch in the rear end.. never heard of a clutch in the rearend maybe you can expand on that as well.. again i do not know much about the f150
 
Last edited:
Messages
14,716
Location
Santa Barbara, CA
 Originally Posted By: mikeg5
 Originally Posted By: punisher
 Originally Posted By: mikeg5
kind of yeah. you can only feel it at take off and thats it. isnt the shaft and all on that ford all sealed?? i dont think there are any grease fitting under that truck. keep in mind i have not been under that truck in a few years. my dad rarely does anything to it other than change the oil.
I'll stand by my previous post.
can you expand on that please? i do not know much about the f150 after speaking with a ford tech he said ujoint or clutch in the rear end.. never heard of a clutch in the rearend maybe you can expand on that as well.. again i do not know much about the f150
it has a clutch type LSD.
 

mikeg5

Thread starter
Messages
1,754
Location
north carolina
 Originally Posted By: bdcardinal
 Originally Posted By: mikeg5
 Originally Posted By: punisher
 Originally Posted By: mikeg5
kind of yeah. you can only feel it at take off and thats it. isnt the shaft and all on that ford all sealed?? i dont think there are any grease fitting under that truck. keep in mind i have not been under that truck in a few years. my dad rarely does anything to it other than change the oil.
I'll stand by my previous post.
can you expand on that please? i do not know much about the f150 after speaking with a ford tech he said ujoint or clutch in the rear end.. never heard of a clutch in the rearend maybe you can expand on that as well.. again i do not know much about the f150
it has a clutch type LSD.
ahh gotcha makes sense now thanks for the clarification
 
Messages
4,434
Location
Massachusetts
 Originally Posted By: Jason2007
Could be that the U-joints are shot or the Traction-Lok unit is wore out or just the fluid is worn out.
You shouldn't feel the LSD while taking off in a straight line on pavement. Pull the rear driveshaft and grease the output splines, as previously mentioned. Check the driveshaft u-joints while it's out.
 

mikeg5

Thread starter
Messages
1,754
Location
north carolina
 Originally Posted By: Zaedock
 Originally Posted By: Jason2007
Could be that the U-joints are shot or the Traction-Lok unit is wore out or just the fluid is worn out.
You shouldn't feel the LSD while taking off in a straight line on pavement. Pull the rear driveshaft and grease the output splines, as previously mentioned. Check the driveshaft u-joints while it's out.
noted thanks!
 

mikeg5

Thread starter
Messages
1,754
Location
north carolina
 Originally Posted By: Zaedock
 Originally Posted By: Jason2007
Could be that the U-joints are shot or the Traction-Lok unit is wore out or just the fluid is worn out.
You shouldn't feel the LSD while taking off in a straight line on pavement. Pull the rear driveshaft and grease the output splines, as previously mentioned. Check the driveshaft u-joints while it's out.
out of curiosity why would you have to grease the splines? its sealed yes? again i am just curious.. trying to learn something
 
Messages
2,439
Location
snowblind in TX
For whatever reason FoMoCo didn't do all of the road testing they should have on that model (no news there if you ever worked on Fords, especially the intro year of a new model or powertrain). There is an incompatability with the grease and whatever metallurgy FoMoCo used on that spline assembly. When you come to a stop, the rear axle rotates forward, effectively lenghtening the driveshaft. When you apply power the splines are under load and bind as the axle rotates under load. Eventually the load overcomes the binding and the whole trans/driveshaft snaps back to it's normal position. Ford just speced another type of grease to alleviate the problem. It has nothing to do with them being sealed, Ford just didn't do their homework on this one.
 

mikeg5

Thread starter
Messages
1,754
Location
north carolina
 Originally Posted By: punisher
For whatever reason FoMoCo didn't do all of the road testing they should have on that model (no news there if you ever worked on Fords, especially the intro year of a new model or powertrain). There is an incompatability with the grease and whatever metallurgy FoMoCo used on that spline assembly. When you come to a stop, the rear axle rotates forward, effectively lenghtening the driveshaft. When you apply power the splines are under load and bind as the axle rotates under load. Eventually the load overcomes the binding and the whole trans/driveshaft snaps back to it's normal position. Ford just speced another type of grease to alleviate the problem. It has nothing to do with them being sealed, Ford just didn't do their homework on this one.
thanks man ill let my dad know before he takes it in
 
Top