Manual shifting harder as car warms

Hello, I have a 2013 fiesta model S sedan with a 5-speed manual. 102k. It shifts normally and easily when car is off or when I start my journey, after a couple of miles the shifter itself becomes a bit harder to move through any gear. They are all equally stiff. After say 5 miles it does take a bit of effort to shift the gears. Once the car cools it's back to normal shifting. There are noises no clunking at any point in the drive. It never slips out of gear. The clutch operation remains the same. The bite point stays in the same place and the pressure required to move it stays the same. I have my transmission fluid filled up to the bottom of the check hole. I have no leaks on the garage floor and I have nothing to wipe off the underneath of the transmission, engine, or at the halfshafts. Clutch fluid is at the level it should be. I will note that some clutch fluid had forced itself out of the container, not sure if that's because I had it filled when it was negative 5 out and right now it's 95 out, not sure if brake fluid /clutch fluid expands that much through a 100° swing. I've had this car many years and it always gets to be 95 in the summer and have never had this shifting issue until a few days ago. Any thoughts or ideas? Thank you very much.

There is a pivot point on the main transmission under that box cover you used to change the (Or Fill Transmission) oil at.

The cover is supposed to protect the area from getting debris and dirt so the pivots and their gymbals can move freely.

When it rains, and there's deep water or very high temperatures, water entry is possible - the gymbals nylon guides can deform - affecting your ability to find the right gear. With the water, rust can form on a main pivot point the shifter uses like a balance arm - to help apply forces from your arm shifting - to the gears and help reduce fatigue when driving in stop-start traffic - keeping it from getting tedious - to a point.

That pivot looks like a E-clip on a shaft that contains that balance arm. It pivots those two cables onto a shaft that translates the motions of those two cables - your input - to a shaft - which slides and rotates to convert your shift pattern into effort the gears that are part of that H-pattern, use to engage and dis-engage from their positions to shift your vehicles gears on the gearbox shafts.

Might want to take that cover off and expose the main shifter-translation assembly so you can look for that E-clip - remove it. Pry the balance arm away - towards you - so you can place a few drops of oil in the hole of that arm to flow lubricant on that pin - then press the balancer arm back into position and re-attach the E-clip. Check shifter operation - if it still binds up - then there is a more serious problem internally and may need more inspection - so be sure to check and refill your oil level in the gearbox - for if it's leaking this hard shifting can lead you down an expensive rabbit hole you don't want to go down.

Thank you for that response. I have gone ahead and done that and will see what happens on my next trip out of town. No leaks at any point. I appreciate you took the time and put some photos. I don't actually have a cover over all of that and perhaps I should try and obtain one.

Quite alright. When you have more time - here are some other troubleshooting hints to help you...

If the transmission side of the shifter seems OK. Lift the car onto jacks - place the transmission in Neutral - keep the Handbrake on while chocking the rear wheels - no need to remove the wheels - just take the weight off the bottom and make it so the wheels can spin freely.

When it's in Neutral - the bigger pivot arm - or club - (what some people look at it as) - you can and should, easily be able to move the arm freely into a Gear using only hand effort. This is done without anyone helping with alignment of the H-pattern but can visually watch the gearshift knob move - rock it left or right to engage the 3rd and 4th gears - someone should be able to see it visually from the drivers side window as it moves forward and back.

• If you can't - Its' possible the cables might be pinched (dislocated) binding or have debris on them - where the sheath that protects the cables - can get bound up by impacts (bending the cables) or thru excessive slack - where the gear shifter guides the make the X-Y motion back at the cabin side - is worn.

If you can - you can also pop off the shifter cable rods by prying off the bushing from the gymbal it's on, and move the shifter cable by hand to make sure it is not sticking. One cable - the one that does that club - will move the Gearshifter forward and back without too much effort - same for the smaller gymbal on the shaft (transmission side) - that bushing you should be able to pull and push and have the Gearshift lever move side to side - again, without too much effort - in the shift ranges of motion.

• If it sticks - might need to remove the Gearshift trim in the cabin, and place drops of oil onto the cables to let it drain down onto - and in thru the cables and their guides / sheath - so oil can penetrate and lubricate the cables to free them up.to restore operation.

So if the shift pattern is fine - but sticks, make sure both the lever in the gearboxs' side and their bushing-ends at the cables - can move freely.

Added:
Basically, were looking ODD-behavior when it's warmed up - so cold temps and it runs alright usually tells me the shifter assembly is the problem - but it can go both ways. One, the shifter assembly in the passenger compartment needs some TLC - else the only other part is the one at the Gearbox. So if you do regular engine-oil changes - take a moment or two to inspect the gearbox shifter assembly and lube it up during that oil change.