[JCPSME]

My Suburban - 97 1500 4x4 5.7vortec 4L60E? automatic - drives/ shifts fine most of the time. I've noticed that after driving above 45-50mph it shifts really hard on the 1-2 shift and fairly hard on the 2-3 shift with light to moderate pressure on the gas pedal. The check engine light is on, they coincide and it used to be intermittent but it's getting to be a regular thing. I borrowed a scanner it showed 1430 0r 1470 (I can't find the paper I wrote them on) that related to the EGR pintail position and it showed a pending code 1860 relating to trans slippage. I've read some of threads on the this problem and the cure for the slipping code is a valve kit from Transgo. Will it cure the hard shifting also? I'm comfortable pulling the valve body off but are there any other recommended repairs/ upgrades with out pulling the trans?
Thanks, Jeff

[Crosley]

yes the P1870 code set and related problems will cause harsh shifting in many cases. THe PCM raises the main line pressure which = harsh shifts.

There may also be broken accumilator springs and the check balls like to wear through the separator plates in these trannys. TransGo has a hardened replacement separtator plate too

There is a TransGo valve kit that will correct this PWM slippage problem in the lock up clutch of the converter.

Depending on the mileage , a full tranny over haul may be recommended, rather than a repair. There may be too much damage to the converter clutch friction material. Pull the pan and see how black stuff is there & how much debris

Originally Posted by JCPSME

My Suburban - 97 1500 4x4 5.7vortec 4L60E? automatic - drives/ shifts fine most of the time. I've noticed that after driving above 45-50mph it shifts really hard on the 1-2 shift and fairly hard on the 2-3 shift with light to moderate pressure on the gas pedal. The check engine light is on, they coincide and it used to be intermittent but it's getting to be a regular thing. I borrowed a scanner it showed 1430 0r 1470 (I can't find the paper I wrote them on) that related to the EGR pintail position and it showed a pending code 1860 relating to trans slippage. I've read some of threads on the this problem and the cure for the slipping code is a valve kit from Transgo. Will it cure the hard shifting also? I'm comfortable pulling the valve body off but are there any other recommended repairs/ upgrades with out pulling the trans?
Thanks, Jeff

[JCPSME]

Thanks Crosley, that's the info I was looking for. On another site they pointed out the ball thru the separator plate problem and a repair kit with a new ball and seat but I'd rather replace the plate and I'll check for broken springs.
I'm not sure about mileage on the transmission but I've got about 180k on the truck, I bought it used. Alot of black stuff in the pan indicates it might need a torque converter also. That makes sense since this problem has become more frequent I've noticed a 15% drop in mileage.
I'd rather not rebuild the transmission but sometimes you gotta do what you gotta do. A friend has a van with the same trans and it lost all forward gears so he would like me to rebuild it for him. Practice makes perfect.
Jeff

[Crosley]

there is a repair insert for the plate check ball hole. They come in a package of 5. TransTec or Teck pak is the name. I use them every day and don't know the correct name... LOL


Repair insert for the check ball May be cheaper or not than the whole plate from TransGo parts distributor.

The converter lock up lining is thin, you will burn it off in no time IF it is slipping more than built in parameters of the PWM system.

IF the 1-2 accumulator piston is plastic... replace it with an aluminum piston!!

[JCPSME]

In another post you mentioned Transgo has valve kits for original and replacement - SERV vbs - are they two separate kits? Sounds like I should go pull the pan before I order any parts. I planned on ordering parts this week and doing the repairs in the next couple of weeks as I have a heavy workload for the next week or two. Thanks Jeff

[Crosley]

There are separate kits from TransGo for the SERV & original v-bodys.


The SERV v-bodys have over sized valves & bores

Originally Posted by JCPSME

In another post you mentioned Transgo has valve kits for original and replacement - SERV vbs - are they two separate kits? Sounds like I should go pull the pan before I order any parts. I planned on ordering parts this week and doing the repairs in the next couple of weeks as I have a heavy workload for the next week or two. Thanks Jeff