LB7: Lockup slipping

Vmyrhaug

2003 lb7sac45 35" 20x12 fjallasport flares
Mar 6, 2016
177
6
18
41
Norway
How many times can the lockup slip before complete trash? Build is in future, hope too drive nice a little longer before build. It's 5. time it has slipped in 3 years now.




Sorry for my bad english. Still a stupid norwegian:)
 

Vmyrhaug

2003 lb7sac45 35" 20x12 fjallasport flares
Mar 6, 2016
177
6
18
41
Norway
5 speed. Tune is around 50hp+ i never tuned it, but it's faster than stock. Hope i can drive it 2000miles with light fot before build. The slip tonight came earlier than before. But its freeking cold outside. -25 degress C. And the temp on trans was low. Have checked the code before, and it was lock up slip. Changed oil, spin on an internial filter 4000miles ago, nothing in filter and oil was good.. i use the truck very light, and its also a low milage. 90000miles and 3900hours on it now..
 

torqued2dmax

Member
Mar 26, 2017
646
1
18
Brookville, PA
5 speed. Tune is around 50hp+ i never tuned it, but it's faster than stock. Hope i can drive it 2000miles with light fot before build. The slip tonight came earlier than before. But its freeking cold outside. -25 degress C. And the temp on trans was low. Have checked the code before, and it was lock up slip. Changed oil, spin on an internial filter 4000miles ago, nothing in filter and oil was good.. i use the truck very light, and its also a low milage. 90000miles and 3900hours on it now..

At -25c I dont know how anything works properly , including me ! But to the point , if $ is a problem right now , when Evan took my trany apart , after it limping several times , he said the clutches looked new , the torque converter was shot though . Since I took it to him for a complete rebuild and 1078 knowing the extra hp I was going to be using I needed the build .You on the other hand might be happy with power where it is right now and if theres not much crap in pan or filters , you might get away with a flush ,new 3 disc converter , filters , fluid . But I would really want you to talk to Evan or Mike on this , I was just giving my own experience with my trany yours might be different ! Good luck though !
 

Vmyrhaug

2003 lb7sac45 35" 20x12 fjallasport flares
Mar 6, 2016
177
6
18
41
Norway
The trans is going too be build, just not $ right now. Plan is too buy kit from evan! I'm going too build it myself, i live in norway and do not trust the builders in this country. Hope it will survive too the summer with very light use..
 

torqued2dmax

Member
Mar 26, 2017
646
1
18
Brookville, PA
The trans is going too be build, just not $ right now. Plan is too buy kit from evan! I'm going too build it myself, i live in norway and do not trust the builders in this country. Hope it will survive too the summer with very light use..

Cant go wrong with his kit , Good luck !
 

Mike L.

Got Sheep?
Staff member
Vendor/Sponsor
Aug 12, 2006
15,681
232
63
Fullerton CA
Perspective and to give good advice? But since you questioned my question instead offering up anything I guess it's a pointless question?

Sent from my SAMSUNG-SM-G900A using Tapatalk

You need to chill out. I asked a simple question.
 

Dozerboy

Well-known member
Jun 23, 2009
4,892
470
83
TX of course
5 speed. Tune is around 50hp+ i never tuned it, but it's faster than stock. Hope i can drive it 2000miles with light fot before build. The slip tonight came earlier than before. But its freeking cold outside. -25 degress C. And the temp on trans was low. Have checked the code before, and it was lock up slip. Changed oil, spin on an internial filter 4000miles ago, nothing in filter and oil was good.. i use the truck very light, and its also a low milage. 90000miles and 3900hours on it now..



Sorry for going off topic. Let me start off by saying I’m not a trans builder. I only know what I’ve read on here. Can you put your truck back to the stock tuning? That would be best. How where you driving when it slipped? I believe the biggest weak point of the 5 speed was was rolling into the throttle in 5th gear hard. The clutches just can’t take the extra power. So be very gentle in 5th maybe even use the overdrive lockout so it stays out of 5th. The trans will get weaker and weaker with every slip. I would think it could last 2000miles or more if you are easy on it. However there is no guarantee. I have no idea one how the trans temp would affect the power holding. I’m sure a very cold trans with thick fluid wouldn’t hold very well, but if the engine was warm at least. I doubt the trans would of been so cold that it would affect power handling much.

You need to chill out. I asked a simple question.



So did I in fact 2. Your response is for me to chill out? You are apparently reading some sort of tone into my response that wasn’t intended. You are extremely knowledgeable trans guy and I’m just some weekend warrior that is only brave enough to install a transgo Jr. in mine. I was really only asking to find out if the power level and generation of trans doesn’t matter.




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Vmyrhaug

2003 lb7sac45 35" 20x12 fjallasport flares
Mar 6, 2016
177
6
18
41
Norway
I dont have anything too set it back to stock tuning... but i'm not hard with the pedal, because i know the trans is weak. It was in 5th gear with lockup, light accelration from 50mph too 60mph on flat road... it was only 5min after the trans came out of cold mode (lockup do not engage before trans it hot enough)
 

wyopoke

wyopoke
Dec 3, 2015
24
0
1
wyoming high country
My suggestion to folks asking Mike or Even questions. Zip it and listen to what they are telling you. If ya don't understand give em a call. Or better yet crate your trans up and call the freight company. I am running Mikes trans, cooler and Evens 1078 convertor couldn't be happier. 1 ton dually, 4x4, twin turbo pushing 750-800 rwhp (little over kill for tow rig). Vmyrhaug, Mike L and Even aren't on here to sell you anything they're here giving free advice based on their years of experience. You can't find two more knowledge guys when it comes to the duramax allison trans.
 

Mike L.

Got Sheep?
Staff member
Vendor/Sponsor
Aug 12, 2006
15,681
232
63
Fullerton CA
My suggestion to folks asking Mike or Even questions. Zip it and listen to what they are telling you. If ya don't understand give em a call. Or better yet crate your trans up and call the freight company. I am running Mikes trans, cooler and Evens 1078 convertor couldn't be happier. 1 ton dually, 4x4, twin turbo pushing 750-800 rwhp (little over kill for tow rig). Vmyrhaug, Mike L and Even aren't on here to sell you anything they're here giving free advice based on their years of experience. You can't find two more knowledge guys when it comes to the duramax allison trans.

Don't mind Dozerboy. He is just an unhappy asshole.:roflmao:
 

Mike L.

Got Sheep?
Staff member
Vendor/Sponsor
Aug 12, 2006
15,681
232
63
Fullerton CA
I dont have anything too set it back to stock tuning... but i'm not hard with the pedal, because i know the trans is weak. It was in 5th gear with lockup, light accelration from 50mph too 60mph on flat road... it was only 5min after the trans came out of cold mode (lockup do not engage before trans it hot enough)

When TCC applies, the mainline pressure drops 100 psi across the board. This does not help clutch holding power.