BajaRunner

I just bought a 1993 chevy 1 ton truck, 4 wheel drive and a 4l80e transmission. Ive put roughly 4000 miles on it since i got it. no problems whatsoever.

Then last night, I was pulling a trailer out in the mud, put it in 4 low, and since i put it back, its doing some crazy stuff.

After unhooking the trailer, I put it back in 2wheel high, and drove to the store. When i pulled up and went to put it in park, the shifter was binding. i played with it for a sec, and it freed up. worked fine I got home and parked it.

I went to move it this morning. didnt feel right with the shifter, but not binding. I parked it, put it in park, and it started rolling down the hill. It wont lock in park now.

is it just an adjustment in the shift linkage, or do i have a bigger problem?

BajaRunner

how do i check that?

Wally

iTrader: (1)

the only thing that plunger would do is not engauge the front axle when put in 4wd.
If you want to test it just unscrew it from the axle and shift into 4wd.....its just a solenoid that moves out or in.
On your trans issue it sounds more like the shift cable may be going bad. I dont believe they have actualy rods like the old trannies did back in the days. Its either that or you mentioned that the truck started rolling when put in park.....in that case it may be the valve body not switching into park mode....i would take it to a trans shop if you know anyone honest that could look at it for ya. It may be as simple as replacing one of the servos in the side of the trans

articfriends

iTrader: (1)

Sounds like a t-case linkage problem or your low range selector fork is bad.Unhook the t-case linkage and rotate shift arm on tcase with pliers. You should be able to put it in 2wd high(which i assume youve already done with the shift lever inside the truck). There are plastic pieces on your t-case shift forks,i would bet the low range fork was damaged already and once you got the hub to slide into low range it didn't slide completely back into hi range even though the other fork shifted it into 2wd.If thats the case then t-case should come out and be inspected,you'll probably need a few seals and a fork. This should not be a real exspensive repair, just rxr labor on t-case and dissasembly/reassembly plus parts,300$-500$ at any HONEST trans shop,Smitty

Wally

iTrader: (1)

Putting the transfercase in neutral will let the truck roll......remember both axles are connected to the transfercase and if its in neutral theres nothing holding the truck back from rolling. The transfer case has to be IN A GEAR and the trans in park for the truck not to roll.

Back to bajarunners shifter issue.......try and check if the neutral saftey switch is working.........Im not sure about your year truck but on my 96 burban its electric via teh brake pedal.....if that goes bad and the system doesnt see that you are pressing the brake it wont let you shift out of park....

BajaRunner

thanks for all the replys. heres some more.

its not the transfer case.

I checked the fluid and it was about 3/4 of a quart low. i topped it off, and the shifter inside the truck is much better.

in forward and reverse no problem. it drives around just like normal. the shifter inside shifts into both, and it drops right in, drives fine.

the problem. when you put it in park, it goes in easier now that i added the fluid, but it will not hold the truck. like its in neutral.

im thinking more like what wally said about a servo inside??? not holding it in park.

any thoughts? is it time to take it to a transmission shop?? or is that something i can replace easily. ive never worked on the guts of one, just dropped the pan and changed filters.

articfriends

iTrader: (1)

There is no servo in trans that has anything to do with park,those pieces are strictly mechanical,a parking pawl that engages with a notched ring gear.The deal with the brake pedal is a mechanical safety interlock that keeps people from bumping shifter out of park (and suing the auto makers).

articfriends

iTrader: (1)

Bajarunner,you got mail. I rebuild transmissions as a business,call me at # i provided and we'll discuss your problem ,Smitty

BajaRunner

Smitty

Thanks for all the advice and phone calls.

Heres the problem

BajaRunner

pulled the pan and found the broken parts, heres the new replacement part. its a shaft that locks the park pawl in