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Ok, excellent Doug I am very surprised on the general condition of this valve body. Perhaps when it got rebuilt they got a low mile unit? either way I recalibrated my vac tester and checked a few more times and was pretty consistent +/- 1"hg. I have a new AFL filter on order as well as a sonnax kit that includes a o-ring plug. Sonnax also makes a o-ringed plug for the AFL but sold out on RA. i am stopping my transmission place this afternoon,I will see if they can order.
Care to share your findings on the 1-2 and 2-3 shift valves? I am surprised Sonnax didn't include any on their vac guide.
Also, stopped by hardware store and picked up a 5/16-18x3/4" set screw. I removed the cup plug in the accumulator housing and tapped it. then installed the set screw with red loctite & staked it. This blocks the 2 holes that can be seen in post #7. The newer style housing does not have these holes. Anyway, I believe I can now omit the PCS accumulator valve & spring. Probably easier to just goto newer housing but saved some coin and I have a feeling I'll be blocking the accumulators on future builds. Did the same for the hole Transgo has you drill for their pressure relief gimmick.
Update on this, got the valve body assembled on saturday and got everything installed. I committed sin and used a HD2 separator plate. I didn't want to or have time to tear into the trans to internally dual feed. Dana had one he could sell me individually so I didn't have to buy a whole kit. Got to filling the trans that night and ran out of fluid, but also noticed the engine was running crappy. while valve body was out had put in new fuel pump, fuel filter and got the injectors professionally cleaned. this morning got fluid and topped up to a point that it was drivable. would barely drive. noticed SES light wasn't coming on AT ALL. in the process of troubleshooting that the negative battery clamped stripped. ended up being a burnt out bulb for the SES. Engine still running crappy, found only 1 injector was working. After some percussive maintenance the injectror began working and was able to go for a drive. I got fluid within the hot range (verified my dip stick while pan was off) but while manually shifting through gears I noticed it would only stay in 2nd briefly and then shift to 3rd WITH THE SHIFT LEVER IN 2. Parked truck and dusted off my laptop and ALDL cable appears I have a code 86 Shift Solenoid B stuck on. Thinking either 2-3 shift valve is stuck or the shift solenoid is stuck in the on position. The shift solenoids are old aftermarket ones, thinking it may be time to upgrade to the latest GM ones.
Any ideas?
Got this sorted out, the HD2 plate from Transgo was manufactured incorrectly. They installed 2 top plates and 1 bottom plate. Trans holds manual 2nd and kicks down properly in OD now. Ended up drilling 2nd 0.082", 3rd 0.093", 4th 0.086". 2nd shift is nice and firm, 4th can somewhat feel with heavy throttle but 3rd is basically stock/soft even at WOT.
Remove 3rd checkball or block 3rd/4th accumulators? Any suggestions?
EDIT: btw, I did the transgo AFL fix as I had the VB out again.
Ya, I guess another reason not to use the Transgo HD2 plate? I've definitely earned this one having had the VB out 3 times. Shout out to Dana @ Probuilt for taking a plate apart and taking calls on a sunday afternoon.
Doug, pretty sure I've made my mind up on dropping the VB again to delete the 3 & 4 accumulators. At WOT you cant even feel the 2-3 shift, just hear the tone of the engine change & tach needle drops. I thought it was slipping at first but after pulling back down into manual 2nd after WOT run I realized it was just in 3rd!
With the orifice sizes you posted earlier in the thread, do you find you need to mess with the tune at all to calm the shifts down at all? 1-2 shift is nice and acceptable currently, if i could get them close to that i'd be pretty happy...
Ya, I guess another reason not to use the Transgo HD2 plate? I've definitely earned this one having had the VB out 3 times. Shout out to Dana @ Probuilt for taking a plate apart and taking calls on a sunday afternoon.
Doug, pretty sure I've made my mind up on dropping the VB again to delete the 3 & 4 accumulators. At WOT you cant even feel the 2-3 shift, just hear the tone of the engine change & tach needle drops. I thought it was slipping at first but after pulling back down into manual 2nd after WOT run I realized it was just in 3rd!
With the orifice sizes you posted earlier in the thread, do you find you need to mess with the tune at all to calm the shifts down at all? 1-2 shift is nice and acceptable currently, if i could get them close to that i'd be pretty happy...
Dana and I just had this same issue with a customer in Canada this Month.
Well thought I'd report back and conclude this thread. I ended up blocking the 3rd & 4th accumulators. I epoxied set screws in the feed holes, left the pistons in with their seals and removed #5 & #6 checkballs. Should have just plugged the exhaust holes in the housing and then could have discarded the pistons all together. If you're not on a budget just get a block off plate (Jake's).
Can actually feel 3rd shift now. If I was to go back in to the unit would try increasing shift hole from 0.093" to 0.101". 4th is a bit to firm compared to the rest of the shifts. I shrunk the shift hole from 0.085" down to 0.067" and glad I did this. If I was to do it again with a new separator plate I'd probably start with stock size 0.050" and adjust from there. Or just leave 4th accumulator active and leave the shift hole in the 0.085" to 0.093" range. I'm gonna try playing with the tune tomorrow, after a few short drives the adaptive learning had already significantly softened up 2nd and 3rd.
Well thought I'd report back and conclude this thread. I ended up blocking the 3rd & 4th accumulators. I epoxied set screws in the feed holes, left the pistons in with their seals and removed #5 & #6 checkballs. Should have just plugged the exhaust holes in the housing and then could have discarded the pistons all together. If you're not on a budget just get a block off plate (Jake's).
Can actually feel 3rd shift now. If I was to go back in to the unit would try increasing shift hole from 0.093" to 0.101". 4th is a bit to firm compared to the rest of the shifts. I shrunk the shift hole from 0.085" down to 0.067" and glad I did this. If I was to do it again with a new separator plate I'd probably start with stock size 0.050" and adjust from there. Or just leave 4th accumulator active and leave the shift hole in the 0.085" to 0.093" range. I'm gonna try playing with the tune tomorrow, after a few short drives the adaptive learning had already significantly softened up 2nd and 3rd.
I am glad to hear it!
I hope our conversations helped things move along in the correct direction.
yes, absolutely! i was being stubborn keeping the HD2 plate and found the problem by accident (and a little bit of luck). learned a lot and gained some more transmission experience on this one. thanks again!
I have temporarily banned someone who was making personal attacks and non-informational posts here and on other threads. If they continue such behavior I was ask the Administrator to permanently ban them.
I apologize for not getting to this quicker. If it happens again, anywhere, with anyone, just send me a message. I immediately then get an email and can deal with it.
Thanks to MaroonMonsterLS1, voretiroc, bbond105 and many others who make this forum informative and helpful to many.
Ted.
Thanks Ted / @mrvedit, that's not the type of post that we like to see, not very helpful. With more and more forum members becoming inactive post like that don't help with keeping members interested. Not to even think what someone new to the forum thinks when post like that are the 1st ones they see.
just recently I have stopped drilling the 1-2 shift orifice in my "750hp recipe" builds. I have been getting occasional complaints of a hard 1-2 despite only a modest line pressure bump (CK purple spring) and this is even with 3000+ stall converters. I have found the ACV bore condition really needs to be good to get best possible shift feel modulation.
no sir for the "750 recipe" I use a stock boost valve. I do check it with a pin gage and a mic the lands and then vac test it once assembled into the stator side of the pump.
I only add the sonnax boost valve beyond that 750hp rating and I add the Jake's PR spring that looks like a th400 spring
no sir for the "750 recipe" I use a stock boost valve. I do check it with a pin gage and a mic the lands and then vac test it once assembled into the stator side of the pump.
I only add the sonnax boost valve beyond that 750hp rating and I add the Jake's PR spring that looks like a th400 spring
i meant the oversized ACV. I have messed with another 4L80E since this thread and also got low vac readings. i see sonnax makes an oversized valve, but the reamer and fixture are $$$
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