I have a Libero GT which came with a 1.8turbo 4wd, i then swapped in a 4g63t from an evo3. The other day I was on the highway in fifth gear coming on and off the gas pedal I may have being doing about 160km and the wheels locked up, when I pulled aside it made a loud noise which seemed to come from the diff. as though it was locking. I came to a complete stop and then put it in 1st gear and everything seemed alright but since then I have been quite sceptical about driving fast in 5th gear. Can anyone give me suggestions to what my problem can be and a solution.

 

Take the diff cover off and have a look inside. It is easier to check then the tranny.

 

I got the diff oil changed and the mechanic said everything seemed well. What should I looking for if the diff. is bad / if the gearbox is bad??