80e Pressure Drop During 1-2 Shift = Cooked Clutches
03-21-2015 | 01:01 PM
#31
Thread Starter
TECH Apprentice
Joined: Jan 2014
Posts: 341
Likes: 0
From: Olathe, KS
I've never understood this.
People that have never even ran Rossler unit's give him undue credit.
I assure you, your transmission is as well built if not better than a Rossler.
I've been into the Rossler units, FLT units, RPM units, and about every other popular builder on the market.
I've been into them all because at some point in time, they all have issues.
There is no other company in the aftermarket performance transmission industry that builds as many 4L80E's as Jake's. Many other companies use parts from Jake's.
The FLT units I've been into appeared to be well done and with FLT's reputation I assume they know what they are doing. They at least didn't have a worn out pump like I've seen from Rossler.
To answer the OP's question. A pressure drop, ONLY on a WOT 1-2 shift, is a fluid pickup issue. PERIOD.
This isn't a build problem.
If the pressure stays steady under all other conditions but at WOT 1-2 (hardest acceleration) it drops, you either don't have enough fluid, or you have a fluid pickup issue from extremely hard acceleration.
We've seen OEM dipsticks off by 3 qts, and the junky braided steel aftermarkets ones off by more than that.
NO BUILDER can overcome low fluid level or other installation issue. It's beyond their control or responsibility.
If you don't verify your dipstick accuracy during install of the transmission, you can never check the fluid level properly.
This is a required step to proper installation and falls on the installer to check it. It does require removing the pan.
1/4" above the pan to case mating flange is where the warm running, full mark should be for a performance unit.
If you have a gauge on the vehicle, and watch the pressure (as you should on a new install), if it drops on a spirited drive, it doesn't have enough fluid or has a pickup issue. PERIOD.
Clutch type, pack clearance, steel type, use of a wavy plate, all has very little effect. These are just steps a good builder uses to have consistent results.
People that have never even ran Rossler unit's give him undue credit.
I assure you, your transmission is as well built if not better than a Rossler.
I've been into the Rossler units, FLT units, RPM units, and about every other popular builder on the market.
I've been into them all because at some point in time, they all have issues.
There is no other company in the aftermarket performance transmission industry that builds as many 4L80E's as Jake's. Many other companies use parts from Jake's.
The FLT units I've been into appeared to be well done and with FLT's reputation I assume they know what they are doing. They at least didn't have a worn out pump like I've seen from Rossler.
To answer the OP's question. A pressure drop, ONLY on a WOT 1-2 shift, is a fluid pickup issue. PERIOD.
This isn't a build problem.
If the pressure stays steady under all other conditions but at WOT 1-2 (hardest acceleration) it drops, you either don't have enough fluid, or you have a fluid pickup issue from extremely hard acceleration.
We've seen OEM dipsticks off by 3 qts, and the junky braided steel aftermarkets ones off by more than that.
NO BUILDER can overcome low fluid level or other installation issue. It's beyond their control or responsibility.
If you don't verify your dipstick accuracy during install of the transmission, you can never check the fluid level properly.
This is a required step to proper installation and falls on the installer to check it. It does require removing the pan.
1/4" above the pan to case mating flange is where the warm running, full mark should be for a performance unit.
If you have a gauge on the vehicle, and watch the pressure (as you should on a new install), if it drops on a spirited drive, it doesn't have enough fluid or has a pickup issue. PERIOD.
Clutch type, pack clearance, steel type, use of a wavy plate, all has very little effect. These are just steps a good builder uses to have consistent results.
To answer your question Pat, it's a stock pan and whatever filter Chuck used, I don't know. I do have a B&M deep pan and new AC Delco filter I wanted my tech to install when he did the swap, but it interferes with my mid pipe and since there are no cats on my truck, no shop will modify my exhaust, so it never got installed.
03-21-2015 | 02:30 PM
#32
This is something I am wondering about on my own 80E that I am installing. Being a 2004 case I grabbed a filter for a 2004 which has bumps on the bottom of it. Went to bolt the pan on and it didn't fit, so I had to use a pre '97 filter which has a flat bottom. Guess I have an old style pan. Filter seems pretty dang tight to the pan.
Top of my dipstick hatch is at least 1/4" below the case/valve body mating surface.
Top of my dipstick hatch is at least 1/4" below the case/valve body mating surface.
03-21-2015 | 02:36 PM
#33
This is something I am wondering about on my own 80E that I am installing. Being a 2004 case I grabbed a filter for a 2004 which has bumps on the bottom of it. Went to bolt the pan on and it didn't fit, so I had to use a pre '97 filter which has a flat bottom. Guess I have an old style pan. Filter seems pretty dang tight to the pan.
Top of my dipstick hatch is at least 1/4" below the case/valve body mating surface.
Top of my dipstick hatch is at least 1/4" below the case/valve body mating surface.
What does the pan look like? Tapered back or not?
Fluid level needs to be at least to the valve body to case seam and or a bit higher as Jake mentioned. And with a stock pan you can launch hard enough to suck air, but in my experience it will show before the 1-2 shift. I suggest everyone runs a pressure gauge and do a hard launch to make sure there isn't a issue. With the right fluid modifications pressure actually has to drop significantly for you to notice a slip. Mine is in the 200 range ( can't remember exactly) at WO.
Last edited by 03sierraslt; 03-21-2015 at 02:42 PM.
03-21-2015 | 03:08 PM
#34
What does the pan look like? Tapered back or not?
Fluid level needs to be at least to the valve body to case seam and or a bit higher as Jake mentioned. And with a stock pan you can launch hard enough to suck air, but in my experience it will show before the 1-2 shift. I suggest everyone runs a pressure gauge and do a hard launch to make sure there isn't a issue. With the right fluid modifications pressure actually has to drop significantly for you to notice a slip. Mine is in the 200 range ( can't remember exactly) at WO.
Fluid level needs to be at least to the valve body to case seam and or a bit higher as Jake mentioned. And with a stock pan you can launch hard enough to suck air, but in my experience it will show before the 1-2 shift. I suggest everyone runs a pressure gauge and do a hard launch to make sure there isn't a issue. With the right fluid modifications pressure actually has to drop significantly for you to notice a slip. Mine is in the 200 range ( can't remember exactly) at WO.
03-21-2015 | 04:42 PM
#36
Thread Starter
TECH Apprentice
Joined: Jan 2014
Posts: 341
Likes: 0
From: Olathe, KS
The FLT units I've been into appeared to be well done and with FLT's reputation I assume they know what they are doing. They at least didn't have a worn out pump like I've seen from Rossler.
To answer the OP's question. A pressure drop, ONLY on a WOT 1-2 shift, is a fluid pickup issue. PERIOD.
This isn't a build problem.
If the pressure stays steady under all other conditions but at WOT 1-2 (hardest acceleration) it drops, you either don't have enough fluid, or you have a fluid pickup issue from extremely hard acceleration.
We've seen OEM dipsticks off by 3 qts, and the junky braided steel aftermarkets ones off by more than that.
NO BUILDER can overcome low fluid level or other installation issue. It's beyond their control or responsibility.
If you don't verify your dipstick accuracy during install of the transmission, you can never check the fluid level properly.
This is a required step to proper installation and falls on the installer to check it. It does require removing the pan.
1/4" above the pan to case mating flange is where the warm running, full mark should be for a performance unit.
If you have a gauge on the vehicle, and watch the pressure (as you should on a new install), if it drops on a spirited drive, it doesn't have enough fluid or has a pickup issue. PERIOD.
To answer the OP's question. A pressure drop, ONLY on a WOT 1-2 shift, is a fluid pickup issue. PERIOD.
This isn't a build problem.
If the pressure stays steady under all other conditions but at WOT 1-2 (hardest acceleration) it drops, you either don't have enough fluid, or you have a fluid pickup issue from extremely hard acceleration.
We've seen OEM dipsticks off by 3 qts, and the junky braided steel aftermarkets ones off by more than that.
NO BUILDER can overcome low fluid level or other installation issue. It's beyond their control or responsibility.
If you don't verify your dipstick accuracy during install of the transmission, you can never check the fluid level properly.
This is a required step to proper installation and falls on the installer to check it. It does require removing the pan.
1/4" above the pan to case mating flange is where the warm running, full mark should be for a performance unit.
If you have a gauge on the vehicle, and watch the pressure (as you should on a new install), if it drops on a spirited drive, it doesn't have enough fluid or has a pickup issue. PERIOD.
So, unfortunately for me, your opinion is incorrect unless there is some other pick up issue, the fluid level is indeed correct and it still has the soft 1-2 @ WOT. In fact, here's a vid I made just as I was leaving the shop...
http://vid1359.photobucket.com/album...321_152559.mp4
This is just my opinion and total speculation: I THINK Chuck tried to save money because this re-build was a warranty issue and re-used the old valve body which was most probably defective electronically. I am assuming his dyno has some sort of manual shift setup since it would need to be interchangeable with several different transmissions - hence the reason for it testing okay at his shop. I could be wrong, but that's what this is looking like in my personal opinion.
03-21-2015 | 04:47 PM
#37
Well, I just returned from my tech's shop, had him drop the pan, pulled and inspected the filter (good seal at inlet and no cracks), bottom of the dipstick was touching the little plate, measurement from the bottom of the dipstick to the mating surface = 1-3/4" + 1/4" = 2", put the filter and pan back on, filled it with dex 6, marked two inches from the bottom of the dipstick on the dipstick and the fluid we put back in was actually right on the new mark. This indicates the additional 2 quarts I put in yesterday was just the correct amount.
So, unfortunately for me, your opinion is incorrect unless there is some other pick up issue, the fluid level is indeed correct and it still has the soft 1-2 @ WOT. In fact, here's a vid I made just as I was leaving the shop...
http://vid1359.photobucket.com/album...321_152559.mp4
This is just my opinion and total speculation: I THINK Chuck tried to save money because this re-build was a warranty issue and re-used the old valve body which was most probably defective electronically. I am assuming his dyno has some sort of manual shift setup since it would need to be interchangeable with several different transmissions - hence the reason for it testing okay at his shop. I could be wrong, but that's what this is looking like in my personal opinion.
So, unfortunately for me, your opinion is incorrect unless there is some other pick up issue, the fluid level is indeed correct and it still has the soft 1-2 @ WOT. In fact, here's a vid I made just as I was leaving the shop...
http://vid1359.photobucket.com/album...321_152559.mp4
This is just my opinion and total speculation: I THINK Chuck tried to save money because this re-build was a warranty issue and re-used the old valve body which was most probably defective electronically. I am assuming his dyno has some sort of manual shift setup since it would need to be interchangeable with several different transmissions - hence the reason for it testing okay at his shop. I could be wrong, but that's what this is looking like in my personal opinion.
03-21-2015 | 05:04 PM
#38
Thread Starter
TECH Apprentice
Joined: Jan 2014
Posts: 341
Likes: 0
From: Olathe, KS
If the trans was burnt up, why does it still shift firm on part throttle? I only drove the truck 2 WOT runs before adding the two quarts as well - If a high performance build can't withstand two runs that's slightly low on fluid, that's pretty sad IMO. Furthermore, Chuck knows I'm a total novice to all this - if it was so extremely important to over fill past the fill line, why did he not tell me to make sure to do that?
03-21-2015 | 05:10 PM
#39
I have a gauge for that
iTrader: (42)
Joined: Jan 2006
Posts: 16,266
Likes: 394
From: Huntsville, AL
Ya know, after listening to it, it really doesnt sound that bad. Have a listen to mine from a couple years ago. This run was like 6.5@112 or something, so about 900ish hp.
I will bet you $50 your intermediates look like this though:
It doesnt take long to toast them with big power/big weight when everything isnt perfect. Pretty much every performance 80e ive heard of has toasty intermediates.
I will bet you $50 your intermediates look like this though:
It doesnt take long to toast them with big power/big weight when everything isnt perfect. Pretty much every performance 80e ive heard of has toasty intermediates.
03-21-2015 | 05:25 PM
#40
I can't answer that for sure, however, it's probably assumed when you're playing at this level that this stuff is understood. There are quite a few critical steps in installing a transmission including the torque converter clearance, using the correcting trans line fittings, proper fluid level, etc. Any of those can result in a failure, and we have seen several cases of these on this forum over the years.