Hard shifting especially hot

[Anthony Defreitas]

I bought my 5-Speed V-6 around a year ago. It has 135,000 miles on it right now. The trans. has always been hard to shift and especially down shifting. This year as the temperatures climbed into the 90's it became downright impossible to shift at times. I have been following the threads on here about trans. fluid being a big part of the problem. Being an old skool guy raised on Municie and T-10 transmissions with good old fashioned rear end fluid I found that hard to believe. I never changed the fluid in manual transmissions and they always shifted smooth as can be. Well, I decided to replace the Trans. fluid using Ford recommended fluid, no fancy stuff. Wow, the transmission now shifts 100 times better than it did when I first got it. Don't get me wrong, power shifting still stinks and It isn't even close to a good old fashioned Muncie but is fun to drive again. Has anyone noticed that anything recently engineered is worse than what was previously used? Even a basic manual trans. suffers the wrath of modern engineering, don't even let me start a conversation on hydraulic clutches!

 

[MasterofDisaster]

I have had a 67 (toploader), 86 & 93 (T-5), and an 08 (TR3650). Toploader was good, the T-5 was ok, although the stock shifter needed work, and TR3650 is good.
I did have a problem with the 08 shifting when it was really cold. Changed to RP synthetic, and shifting got better. I just changed to Mobil 1 this summer, and it's significantly improved over RP.

 

[Craig T Barry]

Mine is a 2008 Shelby and also shifts harder than I’d like. Just had fluid checked and it took one quart buy doesn’t shift any easier. Does RP or others trans fluid really help them shift easier?

 

[Daniel Roberson]

My 2005 GT transmission had to be rebuilt. The shifter that came with these cars sucked. I got an MGW shifter and now I never miss third gear and have no worries about ruining another transmission. You may not want to hear it but you might need your transmission worked on. I couldn't even shift into third gear before my transmission was corrected.

 

[86GT351]

2.7 QTS of Mercon ATF is what is suggested by the manufacturer.

 

[Juice]

Sorry to be the bearer of potentially bad news.
Transmission shifting issues are almost always clutch related. Clutch does not fully release thus, it wont go into gear.
With unkown history of car, this is a concern.
My v6 clutch went at 106,xxx.

 

[dustyn83]

Sometimes, adjusting the clutch will solve this kind of issue.

 

[Juice]

Sometimes, adjusting the clutch will solve this kind of issue.

Clutch is hydraulic. About the only adjustment is shimming the slave cylinder.

 

[Dimontague]

2.7 QTS of Mercon ATF is what is suggested by the manufacturer.

For manual?

Ok i have a 2007 5 speed, 85k miles, about to change fluids. I was checking on best recommendation

Or topping clutch fluid