im-not-guilty

iTrader: (4)

1999 silverado 1500 4x4 old body style 5.7 engine
towed into the shop today
customer installed a used transmission in his driveway and truck would not moved after ....fluid level was OK ..
i disconnected a cooler line at the radiator started engine and no fluid ...
lifted and found a hack install ..t/c was bolted to the flywheel
assumed pump was broken ....
removed trans and flushed cooler ... flow was good ...
removed T/C and no fluid poured out ... removed pump split in 2 and inspected
internals were not cracked as expected ...pressure regulator valve moves ok ...spoke with customer for a little history ....not sure if any of it helps but ...
engine was replaced a year ago ...starter and flywheel were replaced 6 months ago ....trans was replaced 2 months ago and went bad again ...
now were at customer installed current trans ...paper work from the salvage yard says trans was removed from a 1999 tahoe with a 5.7..customer says trans came out of the salvage yards yard truck so they were sure it was good !!!...
5oclock came and im going to play with it again tomorrow ....
any ideas
before i get back on it tomorrow ??
should i have checked a few more things this and payed closer attention to how it came apart yes ...
i just assumed with the scenario it had a busted pump

mrvedit

A busted pump sure was the "obvious" diagnosis.
How about something more basic - since this is a truck it likely has a deep pan - is it possible a car filter was installed or the proper filter clogged completely?
It seems you checked everything else.

im-not-guilty

iTrader: (4)

The pan did not appear to have been removed before install
I cleaned the area around the pan before I opened it up. And their wee no previous signs of removal ...allthought it did have a aftermarket gasket
Would their be a depth issue ??

mrvedit

I was wondering about two possible scenarios:
1. They installed a shallow pan filter it fell out, losing all pressure.
2. They installed a shallow pan filter and the fluid level was too low and below the filter level.

You say "fluid level was OK". Was that your measurement or theirs? Some novice mechanics add fluid to the trans like they would to an engine, leaving it way low.
Either they don't realize you need to start the engine to pump some fluid into the converter and other areas, or they measure it with the engine off which leaves it a good quart+ low.

im-not-guilty

iTrader: (4)

it going back togother now ....new filter is same as the filter that came out ....
just resealed the pump and going to reinstall....paying closer attention ..ill keep you posted

mrvedit

Cool. I'll bet it will work when you put in enough fluid.

im-not-guilty

iTrader: (4)

lets say this was a 4l60 was removed from a nbs 99 truck with a 5.3
and bolted to a 5.7 in a 99 old body style truck ...
is their a difference ??????????????
and how do I tell

9kbd of the tag

mrvedit

All 4L60E with a 300mm input shaft between '98 and '05 are interchangeable, electrically completely identical with only a few minor internal improvement in later years.
Obviously 4L60E with the 298mm input shaft (pre '08, all V6 and SBC engine, and C5 Vette) are incompatible.

im-not-guilty

iTrader: (4)

are the t/c housings the same for 5.3 and 5.7?????????
same depth ??

mrvedit

All converters for 300mm input 4L60E are interchangeable. Same depth.
When converter is fully seated, there should be between 1/16" and 3/16" between the converter pads and the flexplate. I think that is same for all GM setups and likely most other brands too.

im-not-guilty

iTrader: (4)

that's about what I have for a gap
been messing with other stuff ...trans is mated with a few bolts but keep getting side tracked

im-not-guilty

iTrader: (4)

trans is back if far enough so I can started it ......
set to hot fluid level and added additional 2 qts ..........
disconnect line at cooler and still no fluid ........
wtf

mrvedit

Wow, I am also at a loss.
Maybe a clogged or crimped cooler line between the trans and cooler?

Looking through the GM 4l60E Technician's Guide, I see that the feed to the cooler is in the vicinity of the converter clutch valve. Did the converter installing "hacks" remove that valve? It can be checked by only dropping the pan.

I'm really grasping for straws here; you have 100x the experience I do.

im-not-guilty

iTrader: (4)

I have a trans flow machine just do flush and check the flow of the lines and the coolers ...
I connected the machine at the lines where disconnected from the trans and flow is more than acceptable ...
I'm not sure I have 100x the experience u do ...
I probably only average. 5 4l60 repairs a year ...
And their only repairs not overhauls
I work at the dealer and most are under some type of warranty .
Warranty only pays to fix the problem .. Not overhaul

But 5 a year over the last 15 years. Puts me at over 50. ..

I don't know any mods or tips and building tricks ...
They all get fixed with factory parts ...


Just seems this should not be stumping me ..

Pumps not broke
Fluids full
t/c is bolted to flywheel

Doesn't. Appear anyone was in their before me

What's else ??

FLT

iTrader: (1)

Ok, after reading your thread post #7 & #9 are puzzling to me? Can you identify which model trans you have in the truck now? The answer to your question in post #9 is NO, they are different by 1/2 inch. I'm thinking you have a mismatch with the trans or converter possibly, a couple of pics would be helpful in this situation!

Chuck/FLT

im-not-guilty

iTrader: (4)

So if I had a 5.3 trans behind the 5.7
Would the would I have a xtra 1/2 and maybe pulling the t/c out of the pump ?????

mrvedit

Thank you for chiming in Chuck.
I PM'ed the OP that the customer likely hacked something completely unexpected.
Sounds like you suspect the customer tried to use a 298mm converter or a 300mm trans or vice versa.

For those readers not familiar with the difference, here is the 300mm input shaft 4L60E used in all LS-engine vehicles, except for the Vette:



And here is the older style 298mm 4L60E used pre-'98, used in all V6 and SBC engine vehicles and in the C5 Vette:



GM really should have used different part numbers because they are incompatible and use different torque converters, and have a different bell housing depth.

Note that the 300mm 4L60E has a bolt-hole in the 12-O-Clock position and the 298mm model does not.

Also, the 4L65E and 4L70E also have 300mm input shafts and are mechanically interchangeable. To varying extents they are even electrically interchangeable. (I have posted details in other threads.)

FLT

iTrader: (1)

Yes sir! Hopefully the pics above will help you figure it out.

mrvedit

im-not-guilty: sorry I didn't explain this better earlier; it was implied by my comment about the gap between the converter pads and the flexplate. A gap much more than 1/4" will pull the converter out of the pump and generally implies the wrong converter is installed.

im-not-guilty

iTrader: (4)

I have the top one 300mm

Are you guys saying this won't work with a sbc ??

Now here's what may be a catch
Truck is a old body style 99