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97 4L80E dropping out of TC lock up

mannebk said:
i know that Americans are notoriously bad in geography...

the US isn't big enough to drive 5000 miles in a straight line.

from Seattle to Miami is 5500 kilometers, not miles.

and my MH fore sure doesn't float.

so no, i cant drive it in 3rd home and do it im my shop

besides, even if i ship it on a ro-ro the first officer who put a tape measure on my MH would put me right into jail. no way of driving a more than 2,55m wide ting in Europe without special permission, and that's only granted for loads, or farm equipment. both is not what a MH is.
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Carry on
 
GenBiltstein said:
Welcome to my world.
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that's why i now get my self an external pig tail, hook it up, and do my due diligence next.

then i have a clear understanding if the funny behavior comes from inside or outside of the transmission housing. then we move from there.

firing the parts cannon (a full rebuild is nothing else), honestly, every idiot can do that. and because of a lot of idiots doing exactly that, they also get it mostly wrong and mostly introduce more problems than there were in the first place.

its a routine best avoided. with the proverbial one exception. if the cause is a know issue to an established and reproducible problem and the diagnostic work is way more expensive than the part and labor to replace it. that's the only reason one should actually shoot the spare part (minus the s in parts) gun. and if that doesn't fix it, your back to actually doing the diagnostic work for real this time.
 
and just to be precise, you can actually go from Prudhoe Bay Alaska to Key West Floriada and drive 5503 miles in an almost straight line, but it would include a real sizable chunk of Miles driven outside of the US in Canada.... like about a 1/3 of it.
 
an ECM from a 2000 K3500, 4L80E will not work on Your MH ?
I have the stock unit from my truck that I’m saving in case I would ever change my truck back to the GM8 turbo.
If that would work I would mail that to You if You would send it back after the test and diagnosis is complete.
 
it probably would. if yours doesn't have a TCM or TCCM (Transmission Control module or transfer case control modul. but then your controling transmission and engine so its not an ecm engine control module but a pcm a powertrain control module)

but going though the Canadian borde today, i confirmed something. when it its neutralizing in 4th, its actually in somethin similar to 1st. or 2nd and then 1st. but free wheeling when the engine is slower as the vehicle

so i think a broken 1/2 valve spring is fitting that the best.

see the link posted above to the LS place.

all in that's now confirmed the overall best fitting description of my issue.


i think i just drop the pan and pull the 1/2 valve and have a look
 
MrMarty51 said:
an ECM from a 2000 K3500, 4L80E will not work on Your MH ?
I have the stock unit from my truck that I’m saving in case I would ever change my truck back to the GM8 turbo.
If that would work I would mail that to You if You would send it back after the test and diagnosis is complete.
Click to expand...
but if my approach does crapp out, meaning my conclusion was wrong, wouldn't be the first, will for sure eure not be the last time, and/or my then performed pigtail testing will confirm outside of transmission case as reasons for acting up, i would like to come back to your very kind offer. if it then stilk stands, and your obviously welcome to mark your property and tell me what i ow in shipping so i can compensate you when shipping it back.
 
what actually happened is this.

usually i had those issues going down the interstate at 55+ mph... it dropes out of 4th, revs up to 5k untill i stop it by switching it to 3rd.

this time i was just doing 40 when it slipped into 4th while OD was selected. but my first gear usually is a downshift at 35 mph and leads to a bit over 4k rpm of revs... so 40 mph was not at rev limiter jet. close but not at 5k, i think i saw 4800 or so in my ultra gauge.

so it happened the first time, that it slipped out of 4th and revved up towards limiter at 5k but hit the 1st at 4700-4800 foret and actually started to push the car in 1st.

i there for conclude the broken spring in the 1/2 shift spool theory to be confirmed.

and now we know how to test for it too.

very carefully accelerate in OD untill it shifts into 4th, and then let it rev up towards limiter and watch for 1st to engage when engine overtakes the 1st gear st given speed.

i was able to reproduce that at any given try.

not every tim it fell strisg6into 1st, sometimes it was more like second for a few seconds, then it came back to 1st.

sorry for not being mor detailed earlier, i was staying with friends. and still the details of my discovery had to sink in and make sense.

now 3 bottles of wine later i hope I do make sens in my explanations?

does that make any sense to you? am i right about my conclusion about that spring?

sorry, too much wine, cant think straight in 2 languages anymore

good n8 every one
 
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