4l60e Transmission Problem.....

alwcurlz · November 14, 2009

I have a 2000 Chevy S10 Blazer 4x4 4.3V6, 4L60E transmission. The truck has 137,700+ miles on it. The truck drove great when I first bought it. The transmission shifted very well through all the gears, and moving between P/R/D/1/2/3 etc was instant and smooth. Now, however (after checking fluid level and seeing it not on the dipstick, I added nearly a quart of fluid, and) after less than 20 miles of driving tests, it has a long delay before engaging into D (Drive). Everything else works great except moving the shifter into D. It goes into D with a delayed clunk/bang. It seemed to start doing this after I had checked the fluid level and added more fluid because it wasn't showing on the dipstick. It wasn't dextron 3 / III fluid either that I added. Would it cause a problem by adding in 1 qt of another fluid type or is it over-filling? The dipstick showed full. Anyway, the fluid is soaking this square foam thing attached to a vent hose/tube valve which is tied to the transmission dipstick tube and is running down a wire loom, and on top of the exhaust, being smelly of course. The transmission is also apparently a replacement because it is painted gray, and has a Jasper brand sticker on it with a SN: 538283. Also, while under there, I traced the hoses going in and out of the transmission and noticed that there was also a tube attached to the top of the transmission near the bell housing which looks like a short vent tube (?) since one end isn't attached to anything? Questions I have are: Am I overfilling with an incorrect dipstick? The dipstick looks stock and has a GM PN:15153604 on it. Did putting a different transmission fluid cause the strange delay into D? Why is it spewing fluid out of the vent tube near the transmission dipstick tube and, why are there two? vent tubes? Also, the last person who put the pan on put a stupid cork gasket on it which of course is leaking and I'm changing today, along with the filter and correct fluid. I'm also going to replace/update the shift valve to a Corvette version.

Nytemare · November 14, 2009

Did you check/add fluid cold or hot.

Trans has to be warm and vehicle running in park to check the fluid. If there was no fluid on the stick cold you will probably have to add 2-3 quarts or more.

Make sure when you add fluid its running...and after you add each quart of fluid run it through P R N D holding in each for at least 2 seconds.

Bring the level up to between the dots...or on the hash marks..or whatever your truck has as the operating range markings.

alwcurlz · November 14, 2009

Did you check/add fluid cold or hot.
Trans has to be warm and vehicle running in park to check the fluid. If there was no fluid on the stick cold you will probably have to add 2-3 quarts or more.

Make sure when you add fluid its running...and after you add each quart of fluid run it through P R N D holding in each for at least 2 seconds.

Bring the level up to between the dots...or on the hash marks..or whatever your truck has as the operating range markings.

Yeah, I checked the fluid while running after having driven it for a while. I added fluid while it was off. I don't think it would matter though for adding fluid, running or not. I dropped the pan today and drilled a hole, put a 5/8" bolt/nut in place and welded the nut to the outside of the pan. Sure was a mess pulling the pan off while full of fluid. The fluid was fairly dark and quite a bit of silvery slurry in the bottom but no large chips or anything. Going to put the new filter in and bolt the pan back on, then add fluid. Just need to check to see how much goes back in after this.

Nytemare · November 15, 2009

Doesn't make a diff if you add fluid running or not, just that you cannot check the level when not running.

You should do a full flush filter and fill. That way you get all the fluid out. There is only about 3-4 quarts in the pan...there is another 10-12 in the trans its self that you cannot get out without flushing.

One quart of other type fluid shouldn't make any difference. If there wasn't any fluid on the stick it definitely needed at least one quart. Its usually in need of one quart when it is showing add on the dipstick.

It sounds like you built some pressure in the trans for the vent tube to be venting fluid out. I would remove the lines and get them blown out. Take it to a shop and get a full flush and fill, and ask them about the vent tubes while they have it up on the lift. It cost me $120 for a full change, supplying my own oil. They supplied the filter. But it was so much cleaner having them do it...and I had no way of flushing the trans anyway...at that time...I do now.

After the flush everything was so much smoother. They will also take it for a drive before the flush to see how the trans is acting, and tell you if you have any problems.

alwcurlz · November 15, 2009

I finished the oil change on this transmission and added the standard 5 qts of fluid which put it at the add line on the dipstick. It functions better now. I'm going to do other repairs to my truck but, I'll wait a bit to see how much more needs to be added for fluid since it won't be leaking out now with the new gasket. Was nice to be able to put a bolt in the pan for the next fluid change. I drained at least 5 qts out, probably about 6 qts. The next change will be a cinch by just taking out the plug and draining. I've been told that flushing automatic transmissions is not a good idea because it can introduce more problems.

gmtech4 · November 15, 2009

I have to disagree with my friend Aiden ,

transmissions should be checked to full cold running level,there is a hot level but that is checked later after a spin,my point is that oil levels hot is dependent on the trans working or not so cold full is the way to go first ,putting thru the gears is only after its filled not for topping ,only 1 clutch is on in park/neutral I think with out my blue book bible infrt of me,

the hose you felt was the vent on top of it

with oil dark ,don't waste money on servos,its a blazer not a vette lol

I think you MAY have some trouble if its pukin out the dipstick,there is only 1 vent ,

I think you were filling it all wrong and you get a FAIL for that lol

Nytemare · November 15, 2009

My trans dip stick only has two dots on it....full and add...and its a good 3-4" above the full line cold....hmmmm.

The trans shop that did the flush and fill for me also checked it hot and running. And it was a really good shop...the dealerships mechanic actually recommended it because they didn't want to do the flush there because they charge too much....I am a really good customer BTW...and I bring at least 5-7 people in a month to buy a car or truck...so they treat me good.

Who ever told you that flushing a trans will cause troubles is full of it. Changing whats in the pan is like changing your engine oil filter every 3000 miles and topping up the oil.

I've had mine done twice now...its still holding together...and I'm not exactly nice to my trans.

alwcurlz · November 15, 2009

I went and checked again the dipstick and noticed a "cold" spot on the transmission dipstick and higher up a "HOT" in hash marks between two holes. So, from what it says on the stick, check with engine running in park. It would make sense that the level is different when cold as apposed to when it's hot but, I wonder what would be considered "cold". Maybe cold means when it's cold outside? This causes some considerable confusion with different vehicles within the same company (GM). Some have for example, marks on the coolant overflow tank to say "check when hot" and some say "check when cold" Cold meaning it hasn't been started, and is not running. Some have marks for when it's both hot or cold as seen on some power steering sticks, and that's whats on transmission dipstick. When I checked the fluid yesterday after moving the truck outside letting it warm up idling I moved the shift lever to the different selections and noticed it responded more like it should. Guess it was overfilled. I'm thinking when I've been on the road for say 15-25 min at over 50 or 60 mph it'll be "hot". So, the level was actually just below "cold" level on my transmission dipstick which is actually lower than the "hot" level.

Nytemare · November 15, 2009

Hot = Operating temperature

Cold = hasn't been running in a while...usually 2 hrs, and engine temp gauge pointing to lowest temp...and running or not depending on what it tells you to do.

I know your pain with checking fluids....like I said, I have to check my trans Hot and running...it has a full mark and an add mark...no full cold mark. Than Rob says that he has always checked them cold...he used to do this for a living so I'm pretty certain that he knows what he's talking about.

As long as it seems to be working good now...that's the main thing I guess.

alwcurlz · November 15, 2009

Yeah, I'll drive it more and check when it's all good and hot/warm. I used to have a 71 Monte Carlo with the good ol' TH350 and I would check it cold, not running and made my own mark on the stick and it was the same every time on full when running and hot on the hot mark. The oil level in my opinion should be able to be checked when not running/cold but, from examining what I saw underneath, there would be no room for the fluid to settle get an accurate since the fluid is basically filling up the pan and up into the transmission, unlike an engine where it all sits in the bottom pan.

gmtech4 · November 15, 2009

after a rebuild in my bay ,I'd put approx 12 liters ,(tranny dependant) and bring it to full cold ,then run it on the hoist in all gears for a sec,then recheck,road tested 20 km goin thru manual shifting and engine braking and then pin it to see if it will grenade ,lol,take it back and chk it full hot ,kick it to the curb and gets me money lol