When I put my truck in 5th gear it jumps right back out. It still works just like it should if I hold it does anybody know how hard of a fix that would be because I know absolutely nothing about transmissions. Or would it be best to just rebuild the whole thing its a 1988 with 340xxx miles

Marcus should be able to provide some insight I haven't owned a toy in over 12 years.

On my old 05 4x4 yota it got where it wouldn't go into second because the gears were chewed up. Needed a new transmission.

Manual trans are a pretty simple unit. I would have to guess either the dog teeth for the 5th gear is worn OR the synchro is bad, Does it grind going into 5th gear Or does is go in then pop back out grind free?

What year truck and what motor? This will help Identify what transmission you have so I can help diagnose it better.

Alot of people DONT know this but ALL your gears spin as 1 unit ALL the time. When you shift gears your are only engaging dog teeth from each gear to another gear that is connected to the ouput shaft. Synchros is what makes the DOG teeth not Grind each shift. They snychronize the speed of the input to the output so the trans will get into gear properly.

SO when peopl say they chewewd up a Specific GEAR.. most of the time is the dog teeth on the engagement gear.

Put the google on How a manual trasnmission works!

http://auto.howstuffworks.com/transmission.htm

One of my favoriate websites. It has all kinds of interesting stuff on there.

samething happened on my little toyota, it was the synchronizer, but mine did it in 2nd

Put 2 fans face to face and turn one on. Thats a torque converter. How the get them one to one ratio blows my minds

This is a long shot, but... Before you fix the trans, take a look at the frame on the truck. You have a truck that falls in the model year range for a frame warranty buyback. Toyo had a bunch of vehicles with bad frames - excessive rust. They extended the frame warranty to 15 years, no limit on previous owners, no limit on miles. They just bought my '97 4x4 back 2 weeks ago. I had a hole in the frame from sever rust. The truck had 185,000 miles on it. I took it to the local dealership, the service manager looked at it, said yes it qualifies, and submitted the paperwork. I had an offer letter from Toyota via email 3 days later, a check in my hand a week after. They paid me enough to go buy a new MB 45Mag and have beer money for a year left over. They pay 1.5 times book value, and they use a really good book!

http://www.autosafety.org/uploads/phpp6 ... rogram.pdf

I hope this helps.

Rusty frames comes from salt covered roads up north. Everything will rot.

Sounds like I need to take this hunk-a-shit up north and put some miles on it.

Maxis its an 88 with 4 cylinder and it doesn't grind when I put it in gear

You most likely have a W56 transmission. I can just about bet you have a bad Synchro!