Hi guys , well this what i have 1996 sierra 1500 ,with a 305 auto tran. #24203060,, and could B a 4L60E,, the abs lite came on and the anti lock ,,and thats when the trans ,starts to jerk, slip the like hek , going 20mph @ 3-4 thou rpm.. changed abs, lite is out,, antilock lite still onn and not runnig good,,where is the A L sensor ,,what is myy next step,,,,help . JF

Harvey N Tawatao

• 3854 Answers
• Posted on May 06, 2009

SOURCE: WHATS INVOLVED

No that hard, but your going to have to drop the Transmission pan, there are two identical solenoid at the back of the valve body with the pan removed.
The "B" (2-3) solenoid is the closest to the passenger side,"A" (1-2) is closest the driver side.I would go ahead and replace both as they are not that expensive.Spring clips hold them in place that can be removed with a small screw driver.
The "slipping" you're noticing,is most likely just the transmission shift pattern getting screwed up due to the malfunctioning solenoid.Probably more like a 1-2-2-1 or a 4-3-3-4 pattern depending on which way the solenoid is failing,or maybe it feels like it is starting out in 2nd or 3rd gear. 

Once you get the solenoid changed and transmission fluid and filer changed, here is a little added performance you can do. Have the Servos replaced with the Corvette servos, the part is only $45.00 and take about 30 min to replace but less for you since you have the truck up on a lift already. 
Good Luck and here is a link for the 4L60E improvement. http://s-series.org/component/option,com_tech_article/Itemid,/item,6/task,item/

SOURCE: Will a 1994 chevy 4l80e 4wd swap into a 1995 GMC

with a little tooling around im sure itll fit ,you might have to change the tail to trans case then again its a chevy so bolt it in

SOURCE: 1994 Chevy G20 Van - Van (auto trans) only has high (D) gear

Sound like you're going to need to drop the transmission pan so you can replace the filter along with fresh transmission fluid. I had a problem like that many years ago, this correct the problem... I also know that the throttle positioning sensor will also cause transmission shifting problems. I would start with the filter change then go from there... Good luck.

SOURCE: 1993 GMC SIERRA 5.7 4x4,

Good Evening, have you double checked your timing and checked for possible vacuum leaks?

SOURCE: 1997 GMC sierra 1500 5.7 liter. The antilock

clean the mounting surface of the abs sensors.rust builds up under the sensor and it sits too far away from the tone ring causing false abs modulation.