Friends... i bought mehran 2010 1 year ago..through out that period it has been like pain in .......now problem is when on third gear it reaches to 70 km/h, but when I put it on 4rth gear it starts to slowdown. Simply it doesn't eccelerate on 4rth gear.. tunning etc didn't work.. any one knows the solution or has been through this problem. .please share the solution. ..thanks