When my SE is cold it goes into 5th perfectly, but after I've driven the car warm for a while it grinds pretty hard going into 5th. It always goes in, but makes some noise. I changed the trans fluid and no change. I put Lucas 80-90 in it. Anything I could use or add to it to remedy this? Thanks for any help.

 

try atf and pennzoil syncromesh. 50/50.. if that doesn't work, rebuild it

 

Do you have any issues with Reverse?

I ask this because 5th Gear and Reverse are on the same hub and it makes me wonder if that area of the transmission is having issues. It could be simply that your gears aren't messing properly when you shift.

 

the 50/50 mix mentioned above can do a lot to clean the gunk out of the synchros and get things moving correctly again. Good luck...

 

also i have found with the trans fluid low, 5th can have a little grind.. i know you said that you changed the fluid but are you completely sure that its full? as a note, i have used GM's synchromesh with excellent results. i use it exclusively in my 95 Ranger..with 209K. i have not once had a problem with the trans in that truck.

 

I'll try the 50/50 mix this week. I have never had a problem with reverse engaging properly BTW.