1999 Explorer transmission problems

[jtapia36]

i have a 1999 ford explorer. v6 4.0 L. it has just over 134,000 miles on it. when i drive it for more than five or ten miles on the freeway and get off although i'll be stepping on the break, right when i release the pressure on the brake it will go from 500 rpm to 2000 rpm. i took it my auto class and we plugged it into a scanner and the two problems i got were P0734 Gear 4 incorrect, and P0735 Gear 5 incorrect. i have a picture of what the scanner says but i dont know how to put pictures on here. any help would be great. thank you in advance

 

[my98nnj]

Sounds like the brake booster is leaking.

 

[jtapia36]

is there any way to fix that myself or am i going to have to take it into a shop. i leave for school next friday and it's a 450 mile drive so i want to make sure it gets fixed before i leave to be sure that it will last the drive. thank you

 

[gavin]

this may help?
http://www.explorerforum.com/forums/showthread.php?t=259826

I really don't think a brake booster would cause a transmission code