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Additive advice 4l80E 98 Suburban K2500

J

jrsavoie

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Additive advice 4l80E 98 Suburban K2500

The Suburban sat for at least a week. It didn't move forward or back without revving up a significant amount.

It has over 200,000 miles on it now.

Tonight I checked the fluid. It read way over full sitting not having been run or running.

I started it and drove to the house and checked the trans fluid level while running. It was above the bottom mark cold.

This time it took off normally, forward and reverse.

I'm planning to change the fluid with Amsoil transmissioon fluid.

Any other advice I might be interested in hearing? Part number for a trans filter?

Is it even worth changing the filter? Can you clean and reuse them? I have a gasket for some reason.
 
It's always worth changing the filter if you have the pan off and are changing the fluid.

Clean the pan and magnet too.

The metal and o ring gasket is suppose to be reusable, but mine wasn't. It have been on so long it had crushed. A filter usually comes with a replacement gasket.

Don't put addatives in the trans mission. Just like engine oil "additives", they're mostly snake oil or they make you feel that they're doing something (placebo anyone?).

Good ol' quality dexron III or an equivalent is all that's required.
 
My 2 penny's worth is to have the tranny flushed along with the filter change, it replaces most if not all the old fluid with fresh fluid. I had this done 20,000 miles ago with Royal Purples ATF with the piece of mind I don't have to worry about it at all. The filter is only a few bucks and the old one may be the cause of your hesitation you described. ATF is something like 95% detergent to keep everything clean, and if you don't change it when required it varnishes up the inside of the valve body and cause well to make a long story short tranny rebuild.

When I flushed my transmission it took 15 liters I think, and if you were to just to drop the pan replace the filter and gaskets you would only need about 6 liters, in which my mechanic promptly pointed out, it's like pissing in your glass of water and telling yourself it's iced tea as you drink it. In my opinion I would have it flushed and filter and gaskets replaced, hopefully fix your hesitation problem in the process.
 
How much does a fluid flush cost? I had it flushed 100,000 miles ago. Seems ti was pricey even with me suppling the fluid.

I already have the fluid.

With over 200,000 miles is it worth doing a flush?

I still think a remote transmission filter after the cooler is a good Idea. I put one on the 1996 Suburban when I bought it and have been very happy. The fluid has always been clean and that was 150,000 miles ago. It catches way more stuff than the screen in the pan
 
Years back, Bill Heath suggested I put in non-synthetic ATF and add a product called Lube Guard. He told me this was in the transmission when it was new. I flushed the system on my own by draining the fluid, refilling, driving a few days, draining, refilling, etc. about 3-4 times. Upon the last refill is when I added the Lube Guard. I have a large external cooler after the ATF runs through the one in the radiator.

Be careful with a remote filter that you don't reduce the pressure too much. The factory setup should be sufficient. It's lasted you this long, right?

Sitting for a week is not a long time. If I wash my truck and let it sit for a couple weeks, sometimes the drums will rust to the shoes and I'll have to rev pretty high to get it to break loose. Is it something like that, or is it just that the transmission feels "soft" when pulling away? I don't think that's a horrible thing, though, if it's sat for any length of time. I've had a couple vehicles that would do the same thing on a really cold morning. Until the engine had ran for a few minutes, I wasn't moving. One had done that several years and is still on the road today - hasn't been rebuilt.
 
SnowDrift said:
Years back, Bill Heath suggested I put in non-synthetic ATF and add a product called Lube Guard. He told me this was in the transmission when it was new. I flushed the system on my own by draining the fluid, refilling, driving a few days, draining, refilling, etc. about 3-4 times. Upon the last refill is when I added the Lube Guard.
Click to expand...
Had the same advice and it has worked beautifully. I trust the LubeGuard!
 
jrsavoie said:
It wasn't a stuck brake feeling. It was the rev up and go nowhere. Your post makes me feel better.
Click to expand...

Sorry to now make you feel nervous.
My 4L80E did the same as yours. I dropped the pan and changed the filter... there was some metal debris in there.
I then flushed the fluid by unscrewing (at the transmission) the outlet line that goes to the transmission cooler and screwing in a short section of hose that dumped down into a gallon milk container. Start the truck and when the jug is full shut it off and add 4 quarts, start again drain another gallon, add 4, drain 4, add, drain. I ran a case through you can see the color change when the new stuff starts showing up.
Now the bad part. When all done I drove away about 100 yards to a stop sign and that was it, would go no further. Tranny shop told me all the junk in there made things bite and when I flushed to new oil it killed it.
Hope that's not the case with yours as the trans is expensive. I sold my truck instead of fixing it and bought a 6.5 van. A whole new nightmare! but this forum has saved my butt. By the way, 3 months after getting the 6.5 that 4L80E went out. Cost me $2400 to rebuild but I was lucky to find a great shop in RI where it crapped out.
All the best luck!
 
I've heard of that before

Alexe said:
Sorry to now make you feel nervous.
My 4L80E did the same as yours. I dropped the pan and changed the filter... there was some metal debris in there.
I then flushed the fluid by unscrewing (at the transmission) the outlet line that goes to the transmission cooler and screwing in a short section of hose that dumped down into a gallon milk container. Start the truck and when the jug is full shut it off and add 4 quarts, start again drain another gallon, add 4, drain 4, add, drain. I ran a case through you can see the color change when the new stuff starts showing up.
Now the bad part. When all done I drove away about 100 yards to a stop sign and that was it, would go no further. Tranny shop told me all the junk in there made things bite and when I flushed to new oil it killed it.
Hope that's not the case with yours as the trans is expensive. I sold my truck instead of fixing it and bought a 6.5 van. A whole new nightmare! but this forum has saved my butt. By the way, 3 months after getting the 6.5 that 4L80E went out. Cost me $2400 to rebuild but I was lucky to find a great shop in RI where it crapped out.
All the best luck!
Click to expand...
 
According to the website NAPA has it. We actually have a NAPA! I think there are NAPA stores in most country small towns, ours hasnt got most things but they order and it comes in the next morning.
 
Just me or...???

You can call it Carma or Murph's law or what ever but every single time I have dumped the trans fluid on anything with over 100K I have then shortly after been blessed with the opportunity / choice to get the trans rebuilt...:mad2: :eek:
 
Just me or...???
You can call it Carma or Murph's law or what ever but every single time I have dumped the trans fluid on anything with over 100K I have then shortly after been blessed with the opportunity / choice to get the trans rebuilt...


It's not just you. As a 20+ year auto tech I have seen my share of trans issues.

If it is brown or smells burnt and is gritty I won't change it. 100% of the time when changed in that condition within a few weeks the trans gives up the ghost.

People have to remember that trans fluid is mostly a detergent and by changing it in an abused or neglected trans you are cleaning off the clutches and steels to the point that the grit and what was left of the clutch material is now cleaned off to the point of slipping .

It must be changed every 20/30 thou to give max life, especially if towing alot.
 
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