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Transmission core

Stoney

Stoney

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Elmira ny
Ok as most of y'all know. I smoked my tranny a while back. It's @4L80e 1997..
Odds of me ever rebuilding it are slim.. if the new one goes I'm putting the stick shift in.. so my question is how do I sell the core transmission and how much are they worth. .
 
Stoney said:
Ok as most of y'all know. I smoked my tranny a while back. It's @4L80e 1997..
Odds of me ever rebuilding it are slim.. if the new one goes I'm putting the stick shift in.. so my question is how do I sell the core transmission and how much are they worth. .
Click to expand...

Before I canceled my transmission order with the shop in Portland, OR they had a $700 core charge. My mechanic says you can sell the 4L80E for a couple hundred on Craig’s list.

Why did you go with a manual transmission? Those clutches were known to have problems.
 
People that tow over truck weight and try engine braking usually end up with short life from 4l80e. Outside that is when the rig itself is over 14,000 lbs AND it is driven hard.

if you want stick- ok. But if it is a thought that manual is much cheaper long term- we didn’t see that in the fleet. Infact we saw the opposite. And all of the drivers got to choose their truck set up. So it wasn’t a guy abusing clutch because he wanted it to burn out to get a new truck with auto.

Now, many of these trucks were driven harder than average- high mileage. So maybe that was part of it. But I learned that if the 4l80e doesn’t tow a lot- I don’t even change fluid.
Our 01 suburban k2500- it had the trans fluid mistakenly changed at a shop when I dropped off for just engine oil change a hair over 200,000 miles on it. I know all the experts freak out when they hear this. But we had hundreds of trucks crushing 300,000 miles and almost never had any trans issues. Usually input speed sensor or something like that.
 
$100-$200 is about all a core is worth. The 4l80e is not a bad trans, but it has downfalls. The transgo hd2 is a good kit if you're not rebuilding the trans and the sonnax over run kit really helps to strengthen the overdrive roller clutch in 1st-3rd as well as providing engine braking. The AFL valve bore wears rapidly due to GM's narrow land valve design as well as a leak prone tcc valve with no sealing rings. They're also prone to pressure spikes and over pressurization(especially with crap tuning) that can break hard parts. Transgo's popoff valve is a good idea, but in reality is leak prone, and often loses it's seal over time. Sonnax's boost valve with a built in popoff is the preferred solution.

And I still think the biggest problem is a transmission fails, nobody bothers to find why it fails, they just say it's a POS trans, replace/rebuild it, and then blame it when it fails again when in reality the problem was not finding the initial failure which could have been as simple as putting dex vi fluid in to a trans without viton seals.
 
@THEFERMANATOR that is my biggest concern is that something else caused the tranny to fail. I run nothing but dex/merc fluid. Valvoline. I've had a bad intermittent dragging issue with the truck for a long time. Happens on and off all the time.. it actually feels like I'm overpowering the brakes even though I'm not. And when I take foot of throttle it's like a engine brake kicking on. Sitting at red light, sometimes when I take foot off brake the truck takes off without even touching the throttle like it should. Other times I'll take foot off brake and truck doesn't move till I apply throttle.
I don't know if you have followed my saga with it but this problem started after I let a guy do a brake job on the truck. And change tranny fluid and filter. I remember him unplugging a electric plug on the tranny then plugging it back in. Don't remember which plug it was. The problem started as soon as I left . It felt like the brakes were dragging holding the truck back . Kinda the same feeling you have pulling a heavy trailer. I have never smelled the brakes burning at all. And the entire brake system has been rebuilt a couple times trying to figure out the problem. Including the guys on here helping me rebuild it again with all Delco parts.
This truck has always been a power house since I got it.(up until that guy worked on it)... It took off like a Camaro , accelerated quick as heck, and ran like a champ , I could hook any weight to it and it would pull it no problem. And the guys on here had helped me make it even better.
I honestly don't know if prior owner did any modifications that are not visible, to justify how awesome it performed. But after that idiot worked on it that all went to pot. It's never been right since.. I don't think the brakes are causing it because theve been redone multiple times. To no avail, I don't think he screwed anything up changing fluid and filter because that was redone multiple times after by pro mechanic to no avail, (he was also looking to see if he could find anything the other guy may have messed up)..the tranny blew back in October so I put another one in... still have same problem.. so I don't think it is a internal tranny problem ..
only thing my brain comes back to is the plug he pulled. I know he fought with it a little but when I unplugged everything changing the tranny the all unplugged easy and plugged into new tranny easily.. maybe one of the wires pulled loose or something in the plugg when he did it..I'm seriously confused by all of it. Maybe unplugging it erased something in memory of the computer or maybe it's had a tune and unplugging it did something to programming.. ? I have no idea about that kinda stuff ( the computer stuff)..
Any ideas?
As for the core.. I was told it would cost a fortune to rebuild it. I don't know how it's done or if it's something I could do... There was alot of shrapnel in tranny pan so hard parts busted somewhere in there..
If you have advice bid appreciate it
 
I'll add that at times the truck feels like it's old self.. touch the throttle and she's gone. hauling ass no problem.. then 5 minutes later it starts doing the dragging feeling again..and can't get out of its own way..
I will say, I THINK the problem starts after I use the brakes. Then accelerate again. Does anything in the brake system effect the actual tranny? Such as , when you push brake pedal does it send any kind of electrical signal to the tranny for any reason?
 
Stoney said:
I'll add that at times the truck feels like it's old self.. touch the throttle and she's gone. hauling ass no problem.. then 5 minutes later it starts doing the dragging feeling again..and can't get out of its own way..
I will say, I THINK the problem starts after I use the brakes. Then accelerate again. Does anything in the brake system effect the actual tranny? Such as , when you push brake pedal does it send any kind of electrical signal to the tranny for any reason?
Click to expand...

If it were brakes they would be smoking hot. Get an infrared thermometer and check them after a drive.

If it works periodically, sounds more like a problem with fuel or air induction. We have no idea what the truck has got on it because you haven’t put it in your signature line.
 
@Stoney. Jack up all 4 wheels off the ground. Check the front by spinning them by hand stomping the brake pedal and immediately spin them again. If there is a resistance you'll definitely know. For the rear, put the trans in neutral and spin them. Do the same with the brake pedal and see if you feel different resistance or if there stiff to begin with. Then cranking her up making sure the truck is stable and won't fall off the stands, put her in gear and accelerate spinning the rear tires. Hit the brakes then accelerate again. Look for one rear tire not wanting to turn and to other spinning right away as you let off the brake. If one seems to not want to turn, try loosening the shoes by the adjustment through the tiny slotted hole on through the backing plate on that wheel just a tad.

If you find that it takes them a bit of time to fully release the brake after letting off the pedal, there'll be a problem with ether the brake hose, wheel cylinders, or something up front like the master cylinder or proportioning valve (built into the ABS unit) causing a slow release.
 
If using jack stands. Place some good boards under each stand if they are not going on concrete. Even on asphalt they will sink in amd tip over.
I have pieces of plywood cut that are just a little larger that the base of the jack stands. Leveling the ground where each stand is going to be places then placing the plywood down and the stand atop of that.
Just be safe whatever You do.
 
Are you sure he didn’t bend a pin in the connector or one of the pins popped out?
If the problem definitely started when they messed with it that day- examine each thing they messed with in detail.
Everything else you mess with besides that just adds confusion to it.
 
Will L. said:
Are you sure he didn’t bend a pin in the connector or one of the pins popped out?
If the problem definitely started when they messed with it that day- examine each thing they messed with in detail.
Everything else you mess with besides that just adds confusion to it.
Click to expand...
I thought that He had mentioned that He had done that.
To Me, checking each pin would be to pull apart the plugs, grab each individual pin connector with a pair of needle nose pliers then oulling and pushing, inwards and outwards on each one to test that they each one is secure in their individual socket.
Then on the other side, grabbing each wire and pulling/pushing to make sure none of those had let loose in their individual compartment.
 
I'll pull the plug off tomorrow and look. Full disclosure. Back brakes are completely disconnected right now. Brake line is cut and pinched about a foot south of abs box.. few days ago when I was working on the one caliper ( the one that broke the slider bolt) (btw still can't fix that because can't get spindle/hub anywhere) anyhow I put it back together the best I could..(I know, not safe) anyhow when I went to bleed the brakes I was pumping them up and heard fluid falling out from under truck About half way back. Got under there , mine line down the frame had blown out.. can't get new line till Tuesday. So I cut it up by abs and pinched it off . So back brakes are completely disconnected.. so can't be them since it's still doing same thing with them not hooked up.
What is proportioning valve? And what does it do?.. I'd considered deleting abs because I hate abs.. it's completely unplugged anyhow.. did that a couple months ago but that didn't change anything either...
Since @Will L. Said to check pins can I safely assume that yes in fact theres something that can happen electrical that would cause this?
Can proportioning valve still cause problems with abs disconnected?
 
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