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H3 Stall speed in trans

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
I read on an old thread that the stall speed is near 1450 on the I-5 H3. Is this the same on the alpha? I had my trans rebuilt and I think the bastard put in the wrong stall speed. Trans is running hotter then ever before. Tested stall speed by foot on brake and gas till it won't raise anymore and it's shows 1800-1900.

If my stall is 1800-1900 stall
Stock Chevy 1500 is 1600
H3 1450...

That would explain my issues. Is the alpha using the same stall?
 

GreatDaneHummer

Well-Known Member
Messages
994
Location
Chicago
When I purchased my PATC transmission they asked which engine I had and when I told them the I5 they recommended the 1600 instead of the 1800 they put for the V8. I hope that helps.
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
Thanks, I also got another response via text saying 1800, maybe they put a 1450 in it on accident after the V8 swap?
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
I wish I went GM reman instead of this yahoo rebuilding it.

My original trans didn't have to be rebuilt it still worked great at 135k miles. When I did the V8 swap I had to swap the bellhousing and it was already out so I said why not...had it rebuilt and it kicked ass! Typical 4l60e upgrades. Then I lost a trans line and burnt up the trans. Had the same guy rebuild it and this time it has more delay and requires more throttle input and has way more heat. I'm curious if the first time around he used a I5 stall and this time a V8 stall? Who knows I'm going to call him
 

CaseyS

Well-Known Member
Messages
731
Location
Louisiana
I5 and v8 each use a totally different converter. No way to cross them up.

Did he actually change the converter on the last rebuild?

When and where are you seeing higher temps? Off road, normal driving, converter locked or unlocked?
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
I would hope he did Casey but I'm not sure. I'm seeing higher temps all the way around. On road, off-road, during normal driving. It doesn't seem to matter what I'm doing, if I'm moving temps are running hotter then ever before.
 

rsc

Well-Known Member
Messages
1,087
Location
Tulsa
I could see a higher stall causing heat buildup around town, but once the converter locks up above 45 mph then it shouldn't be an issue right? A V8 should easily pull a lower converter stall, unless the early lock up puts too much stress on transmission components? I really don't know enough about automatics, hence why I now have a 5 speed.
 

Kyle

Well-Known Member
Messages
1,707
Location
Santa Clarita, CA
I could see a higher stall causing heat buildup around town, but once the converter locks up above 45 mph then it shouldn't be an issue right? A V8 should easily pull a lower converter stall, unless the early lock up puts too much stress on transmission components? I really don't know enough about automatics, hence why I now have a 5 speed.
i know with the I5 and 35's the lock up occurs way to early and really starts lugging the engine. i usually put my foot into it to get it out of over drive and shift to 3rd.
 

amrg

Well-Known Member
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What trans temps are you seeing exactly?
If you are running an external trans cooler, check its not clogged or the hoses bent. I don't even know if air can be trapped in it.
Im running a 3200K stall speed and highway temps are really low 120* in our warm 65* winters .

Anyway, the alpha stalls at 1800 rpms. The I5 stalls at around 2500. (Thats the rpm speed I used to get immediately when I floor it)
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
Nope these measurements are with 40s and old trans and 40s with rebuilt trans.

Bypassed oem cooler with 160 thermostat and details cooler.

Old trans ran at 168 cruising down the highway, new trans 174-176 if I was running hard the old trans would go over 170 but cool back down quickly.

Off-road crawling in rocks 168 always no matter how I pushed it. New one I was running 180-186.

Street driving in 100 degree weather pushing it I could hit 190. Street driving in 75 degree weather Can hit 205 and still climbing until I turn it off.

Off road high speed in sand in hot weather pushing it hard Was the only time I could get the old trans over 200. The new one I feel I can get the trans over 200 in any situation except freeway cruising (haven't been in 100+ yet but can probably hit 200 plus on the freeway when it gets hotter) the only difference between old and new is the actual trans and thermostat location. Thermostat with old one was mounted by the bumper new trans has thermostat mounted off the framerail for a cleaner look but can go back if necessary.

Only other thing I can think of is reversed trans lines? I can double check that when I get home but I'm 99% sure it's correct
 

amrg

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What was the reason for your rebuild?
Did you replace the cooler after the rebuild? If not then If there were debris in the oil previously (if something broke) is it possible they clogged partially the cooler lines reducing cooler efficiency?
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
Rebuild was because I lost a transmission line and lost all fluid and burnt the trans I had a new cooler after the rebuild but when I ran hot I put the old one in thinking that new cooler wasnt as good
 

rsc

Well-Known Member
Messages
1,087
Location
Tulsa
I'm going to make a guess that you haven't changed from a ScanGauge to a mechanical gauge to get the readings, but I wonder if the temp sender in the trans. needs to be replaced. Could the calibration be off after you cooked the trans before?
 

4speedfunk

Well-Known Member
Messages
4,212
Location
Tardville
Pedal set from a Colorado/Canyon...plasma a hole in the floor...grab a manual gearbox from something GM...be done with it.


Sent from my iPhone using Tapatalk
 

Kyle

Well-Known Member
Messages
1,707
Location
Santa Clarita, CA
That's where I'm heading 4 speed lol less crap to go wrong
i was actually just thinking about this, i wonder how hard it would be, i assume just adding a clutch pedal, clutch master cylinder, run the cable and bolt on the trans. Then reprogram the computer.
 
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amrg

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Saying it that way makes it sound easy but you need to take into considerations so many things!
Transfer case bolting up, front and rear drive shaft lengths, trans mounts and offcourse if the space exists for it in the trans tunnel. After that you will need the shifter to come up in the right place (or close to it) and then you are probably good to go. Tunning is actually the easiest part of it!
 

Kyle

Well-Known Member
Messages
1,707
Location
Santa Clarita, CA
Saying it that way makes it sound easy but you need to take into considerations so many things!
Transfer case bolting up, front and rear drive shaft lengths, trans mounts and offcourse if the space exists for it in the trans tunnel. After that you will need the shifter to come up in the right place (or close to it) and then you are probably good to go. Tunning is actually the easiest part of it!
oh im sure it will be a lot of work, the h3 did come with a manual trans, so i assume everything will theoretically "bolt in".
 

amrg

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The ar5 manual was for the I5. On the V8 would it hold? Esp since its rated at 260 ft.lb
But you are right if someone wanted to instal that trans they can since it was there stock. Just need a bellhousing to have it mount on the V8.
It does have deeper gears making it easier on the acceleration.
 

amrg

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Im not sure but I believe all manual 6l80s came in 2wd.
Now its possible to convert a 2wd auto to a 4wd, but the manual?
Obviously you will have to do all the leg work. An auto 6l80e been done and documented, a manual not yet.
 
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