Like_A_Rock

While driving down the road today, I slowed down for a turn, the truck shifted down to 2nd (as normal) and then as I accelerated after the turn the truck went to shift into 3rd... and it was like I droped it in neutral. It shifts just fine from 1st to 2nd, but is like I dont have a 3rd gear. No difference in D or O/D, Reverse works fine and the manual 1st and 2nd gears work fine (I limped it home in manual 2nd). Its not like I was trying to do a 3rd gear burnout or anything, I was just cruising. Unfortunetly I had the radio going so I didnt hear anything. I was wondering if I tosted one of the clutches or mabey a silinoid whent bad? Any idea's?

RacerX

What year is it? They didnt put solenoid valve body in the C/K until 1992-3 model year. You should check for kickdown lever mechanical connection on the left side of the TBI. If this linkage goes then you lose pressure in the transmission and burn up 3 gear clutches. Also make sure your electrical connections are good at the VSS on the tailshaft. Check your fluid and make sure level is good and color is better. Dark brown no good, bright red excellent.

Like_A_Rock

Its an '88. I just got off work early so I'm gona go take a look at the things you mentioned.

Like_A_Rock

Well I took a look at the things you mentioned. The only thing I found wrong was the ATF level. I checked it as the dip stick instructed, with the truck idoling in park and hot. It was at the add line. The fluid looks decent, and it should sence I changed it a little more than a year ago. Now while trying to determin where all the ATF whent has me stumped. asside from a little dirt on the pan, its clean, and all the bolts are nice and snug, so no leaks there. Same with the input shaft (from trans to torque converter), asside from dirt, its clean. I found ATF in 2 places. I found a little on the plug for the sensor you had mentioned. Not so much on the sensor, just the plug. And I also found ATF on the U-Joint. The actual output shaft is perfectly dry and clean, as well as everything around it. Just the U-joint is wet. I drew up a pic on MS Paint to give you an idea if I'm not typing clear enough.
Other than filling it back up with ATF, any sugestions?

RacerX

Well, then its most likely an internal problem. If you cannot upshift from 2-3 nor 3-4 then you can do a pressure test if you have a oil pressure gauge. But generallly speaking, its best to prepare for the worst if the problem is inside the trans. The best thing is that you can get one for $600 if you re willing to put it in yourself.

Like_A_Rock

OK, its internal. 3rd and 4th gears are gone. I filled it up to the full mark and it made no difference. How much and how difficult is it to rebuild a 700r4? And would I need any specalty tools?

RacerX

Silverado on here put me onto a book he got off Amazon. Contains all the tricks for 4L60s.

I have ATRA books myself. But I use the GM Service Manual for the G Van. Books on Ebay by the dozen.

About $1300 to rebuild. Or $6-700 for a rebuilt unit if you want to do the R/R yourself or with a buddy on the weekend. Not hard at all.

Like_A_Rock

oh shiz, I was looking at the $180 - $250 "rebuild kits" on summit

RacerX

Those are kits to rebuild the trans. but you still have to disassemble it to get the clutches in there. If you just want it done already there are 2 options: a. pay someone to build it and R/R; or
b.pay them to rebuild it & just R/R it yourself.

Like_A_Rock

I want to do the work my self, but IDK if my dad would be OK with me doing that. He gets concerned ever time I opened the hood.