[4.8t]

ok, so my trans in my tahoe took a dump of some sort today. it was drving fine got to a friends house turned it off. about 20mins later went out to move it, put it in reverse and it would not go. it does not free rev its like i'm brake stalling. it will rev up to about 3500 rpm (has a yank tt3000 stall) but it takes over half throttle to get it up that high and it spools the turbo. just like brake stalling. when in drive it goes forward but it take alot of gas to get it going. putting it in first it acts like reverse does. 2,3,and OD will let it go foward but like i said it takes a heavy foot to get it going. funny thing if you put it in nuetral and rev it up, it will try to move forward. not fast or anything and it does free rev but it rocks forward. so what can cause this? just maybe 3 miles before we got to the house we used reverse and it worked fine.

please help,
Mike

[Crosley]

Originally Posted by 4.8t

ok, so my trans in my tahoe took a dump of some sort today. it was drving fine got to a friends house turned it off. about 20mins later went out to move it, put it in reverse and it would not go. it does not free rev its like i'm brake stalling. it will rev up to about 3500 rpm (has a yank tt3000 stall) but it takes over half throttle to get it up that high and it spools the turbo. just like brake stalling. when in drive it goes forward but it take alot of gas to get it going. putting it in first it acts like reverse does. 2,3,and OD will let it go foward but like i said it takes a heavy foot to get it going. funny thing if you put it in nuetral and rev it up, it will try to move forward. not fast or anything and it does free rev but it rocks forward. so what can cause this? just maybe 3 miles before we got to the house we used reverse and it worked fine.

please help,
Mike

year of vehicle?

Mileage on the trans?

Any mods to the trans for this turbo setup?

Since this vehicle is turbo'd,, I guess you have custom programming?

Check engine light "on" in the dash?

Any codes pulled yet?

It sounds like a mechanical failure inside the trans , not an electronic problem from your description

[4.8t]

Originally Posted by Crosley

year of vehicle?

Mileage on the trans?

Any mods to the trans for this turbo setup?

Since this vehicle is turbo'd,, I guess you have custom programming?

Check engine light "on" in the dash?

Any codes pulled yet?

It sounds like a mechanical failure inside the trans , not an electronic problem from your description

2004 tahoe with 75000 miles. i drilled the seperator plate just a bit for a better 1-2 shift. followed instructions in transgo hd2 shift kit. did not however install the shift kit. i bought a used 4thgear servo and a 2nd gear servo and corrvette pin. and installed all of it. the guy gave it to me in the hd2 box which had some stuff left over from his install. basically everything he could take out of his trans. it has a yank tt3000. i use hptuners to tune the truck. no codes at all that was the first thing i checked. only other mods is the detroit locker in the rear. this thing has never slipes and has alway hit the gears just right. but here latly it has been not wanting to shift to first comeing to a stop but not stoping completely. kinda like rolling a stop sign type stuff.

any other questions just ask i'll answer best i can.

could it be that plastic accumilator piston?

TCC locks up just fine. incase it matters.

oh yeah and i found some fluid coming out of the vent tube. i thought it was my transfer case then finally found the little guy (vent tube) sitting right on top of it.

[Crosley]

I never use plastic pistons.. they break.

[33mopower]

The tranny in my 96 tahoe (4l60e) did exactly the same thing when it went out.

[4.8t]

if that little thing broke would it cause my problem? also if your cruising about 15mph and put it in first. it acts like someone hit the brakes and brings you to a stop. rather fast

[Crosley]

Drop the trans pan... remove the 1-2 accumulator housing and check it.