Tips for how to drive a fat-ass truck without blowing up the tranny or rear end?
10-01-2005, 01:24 AM
#11
TECH Veteran
Thread Starter
Damn, James, there you go raining on my parade. Again. 
Of course, you are correct....my setup will not allow me to drive however I want with impunity. I know this, and I choose to live with it. Until such time that I either upgrade the tranny & axle, or get another vehicle with which to get my *******, this is all I got.
So, what I am asking is, given what I have (4L65E with shift kit, 8.6" ring gear), what are some things should watch out for, or be careful of, when driving this beast around? That is really what I am after here.
Of course, you are correct....my setup will not allow me to drive however I want with impunity. I know this, and I choose to live with it. Until such time that I either upgrade the tranny & axle, or get another vehicle with which to get my *******, this is all I got.
So, what I am asking is, given what I have (4L65E with shift kit, 8.6" ring gear), what are some things should watch out for, or be careful of, when driving this beast around? That is really what I am after here.
10-01-2005, 11:26 AM
#12
This is the main reason I decided to live with the weight penalty of the 2500HD series chassis over the 1500 series chassis. Even still, it needed some upgrades to make it more tolerable to the things I had planned for it.
That said, after the shift kit and detroit locker was installed all has been well. I have over 80 1/4 mile passes and 12,000 supercharged miles and its holding together quite well.
That said, after the shift kit and detroit locker was installed all has been well. I have over 80 1/4 mile passes and 12,000 supercharged miles and its holding together quite well.
Originally Posted by James B.
A 4-2 downshift is a single event: 3-4 clutchpack disengage, and no overrun clutches are active so overrun is allowed. A 3-2 downshift is the most technically complex - band must engage while 3-4 clutch pack disengages. There is even a solenoid dedicated to this downshift.
Back to the original discussion...
The SUVs have so much more weight over the rear end that they cannot be compared to pickups for what holds up and what doesn't. The weight makes traction and it's that combined with torque that tears stuff up.
The 4L60/65-E only has a chance of providing 5-digits of miles service if it is set up never to shift hard. Shifts can be firm but should not jolt under any throttle conditions.
At some point though you'll probably come to the unfortunate realization that any trans based on the 700R4 and any rear end with a ring gear smaller than 9.5" will not let you drive it the way you really want to. Both components are rated far too low to handle the torque a blown motor makes.
It has taken a lot of patience and investment to get my own rig's drivetrain to hold up to the way I drive. I'm lucky to get 10,000 miles out of a set of tires. It would not have been possible with any kind of 10-bolt or anybody's 4L60/65 transmission.
Back to the original discussion...
The SUVs have so much more weight over the rear end that they cannot be compared to pickups for what holds up and what doesn't. The weight makes traction and it's that combined with torque that tears stuff up.
The 4L60/65-E only has a chance of providing 5-digits of miles service if it is set up never to shift hard. Shifts can be firm but should not jolt under any throttle conditions.
At some point though you'll probably come to the unfortunate realization that any trans based on the 700R4 and any rear end with a ring gear smaller than 9.5" will not let you drive it the way you really want to. Both components are rated far too low to handle the torque a blown motor makes.
It has taken a lot of patience and investment to get my own rig's drivetrain to hold up to the way I drive. I'm lucky to get 10,000 miles out of a set of tires. It would not have been possible with any kind of 10-bolt or anybody's 4L60/65 transmission.
10-01-2005, 03:31 PM
#13
Originally Posted by Naked AV
...what are some things should watch out for, or be careful of, when driving this beast around? That is really what I am after here.
Minimize the number of WOT 2-3 upshifts. The 3-4 clutch pack is the most overworked friction component in the trans. If you baby the 2-3 shifts it will help those last longer.
Minimize WOT in first gear. In first, torque multiplication is greatest. It is in first gear the rear end is in the most danger.
When traction is poor do not exploit the opportunity to spin the tires. Even though you know you can, at some point the G80 is going to kick in and try to stop the slip. The instantaneous load the carrier has to stand up to when a tire is spinning in first gear is sometimes enough to explode the differential.
Keep it under 110MPH. The stock GM driveshaft is not balanced well enough for high-speed. If your upper speed governor has been lifted or increased keep this in mind.
When doing burnouts, use first gear. This prevents upshift-downshift-upshift when doing it. Rapid sequential upshifts and downshifts drains the accummulators faster than pump can supply fluid. The loss in line pressure results in slow band engagement which can result in a burnt band. If it's going back and forth between second and third you're screwed for sure. That will easily burn the 3-4 pack.
Refrain from lighting up the tires when pulling into a right turn. I know it's tempingting, I do it all the time. This is hell on the differential and a 10-bolt under a 6Klbs. truck cannot take it.
10-01-2005, 03:56 PM
#14
TECH Veteran
Thread Starter
Originally Posted by James B.
Okay, I can offer some of that...
Minimize the number of WOT 2-3 upshifts. The 3-4 clutch pack is the most overworked friction component in the trans. If you baby the 2-3 shifts it will help those last longer.
Minimize the number of WOT 2-3 upshifts. The 3-4 clutch pack is the most overworked friction component in the trans. If you baby the 2-3 shifts it will help those last longer.
Originally Posted by James B.
Minimize WOT in first gear. In first, torque multiplication is greatest. It is in first gear the rear end is in the most danger.
Originally Posted by James B.
When traction is poor do not exploit the opportunity to spin the tires. Even though you know you can, at some point the G80 is going to kick in and try to stop the slip. The instantaneous load the carrier has to stand up to when a tire is spinning in first gear is sometimes enough to explode the differential.
Originally Posted by James B.
Keep it under 110MPH. The stock GM driveshaft is not balanced well enough for high-speed. If your upper speed governor has been lifted or increased keep this in mind.
Originally Posted by James B.
When doing burnouts, use first gear. This prevents upshift-downshift-upshift when doing it. Rapid sequential upshifts and downshifts drains the accummulators faster than pump can supply fluid. The loss in line pressure results in slow band engagement which can result in a burnt band. If it's going back and forth between second and third you're screwed for sure. That will easily burn the 3-4 pack.
Originally Posted by James B.
Refrain from lighting up the tires when pulling into a right turn. I know it's tempingting, I do it all the time. This is hell on the differential and a 10-bolt under a 6Klbs. truck cannot take it.
Also, is it just right-hand turns, or both right-hand and left-hand turns you are talking about?
Thanks for your tips, they are greatly appreciated.
10-02-2005, 12:23 PM
#15
You have an Eaton Posi, cool. I wasn't paying much attention to sigs when I started blabbling.
The Eaton LSD emilinates the fear of spinning tires suddenly locking up because it works different. The G80 RESPONDS to tirespin already taking place where the Eaton PREVENTS it from happening in the first place. Besides a superior design for high horsepower, they are built to hold more torque.
The Eaton helps ALOT but it can't make the 10-bolt bullit-proof. The center differential case is weak. It actually flexes. In first gear especially, the amount of torque being applied to the axles is also applied to the differential case in the opposite direction. You also get the force of the wheels pushing the vehicle forward. Combined, it causes the center section to distort - it spreads apart. When this happens the contact pattern between the ring and pinion gears changes and more force gets moved to the tips of the teeth. That can break the teeth off. The first signs this is happening will be leaks coming from the cover. The movement will cause the cover bolts to walk out. This was happening to me for a few months up until the day the whole thing exploded.
The Eaton LSD emilinates the fear of spinning tires suddenly locking up because it works different. The G80 RESPONDS to tirespin already taking place where the Eaton PREVENTS it from happening in the first place. Besides a superior design for high horsepower, they are built to hold more torque.
The Eaton helps ALOT but it can't make the 10-bolt bullit-proof. The center differential case is weak. It actually flexes. In first gear especially, the amount of torque being applied to the axles is also applied to the differential case in the opposite direction. You also get the force of the wheels pushing the vehicle forward. Combined, it causes the center section to distort - it spreads apart. When this happens the contact pattern between the ring and pinion gears changes and more force gets moved to the tips of the teeth. That can break the teeth off. The first signs this is happening will be leaks coming from the cover. The movement will cause the cover bolts to walk out. This was happening to me for a few months up until the day the whole thing exploded.
10-02-2005, 12:48 PM
#16
TECH Veteran
Thread Starter
Originally Posted by James B.
You have an Eaton Posi, cool. I wasn't paying much attention to sigs when I started blabbling.
The Eaton LSD emilinates the fear of spinning tires suddenly locking up because it works different. The G80 RESPONDS to tirespin already taking place where the Eaton PREVENTS it from happening in the first place. Besides a superior design for high horsepower, they are built to hold more torque.
The Eaton helps ALOT but it can't make the 10-bolt bullit-proof. The center differential case is weak. It actually flexes. In first gear especially, the amount of torque being applied to the axles is also applied to the differential case in the opposite direction. You also get the force of the wheels pushing the vehicle forward. Combined, it causes the center section to distort - it spreads apart. When this happens the contact pattern between the ring and pinion gears changes and more force gets moved to the tips of the teeth. That can break the teeth off. The first signs this is happening will be leaks coming from the cover. The movement will cause the cover bolts to walk out. This was happening to me for a few months up until the day the whole thing exploded.
The Eaton LSD emilinates the fear of spinning tires suddenly locking up because it works different. The G80 RESPONDS to tirespin already taking place where the Eaton PREVENTS it from happening in the first place. Besides a superior design for high horsepower, they are built to hold more torque.
The Eaton helps ALOT but it can't make the 10-bolt bullit-proof. The center differential case is weak. It actually flexes. In first gear especially, the amount of torque being applied to the axles is also applied to the differential case in the opposite direction. You also get the force of the wheels pushing the vehicle forward. Combined, it causes the center section to distort - it spreads apart. When this happens the contact pattern between the ring and pinion gears changes and more force gets moved to the tips of the teeth. That can break the teeth off. The first signs this is happening will be leaks coming from the cover. The movement will cause the cover bolts to walk out. This was happening to me for a few months up until the day the whole thing exploded.
And I'm curious, what is your opinion on the T/A covers that preload the carrier?
10-02-2005, 01:02 PM
#17
Originally Posted by Naked AV
When you blew up your rear, did it have a G80 in there?
Originally Posted by Naked AV
And I'm curious, what is your opinion on the T/A covers that preload the carrier?
I've always like the design of the Mag-Hytec covers. They don't preload, however. They use an o-ring ina reverse v-groove in the cover to seal - no gasket. That allows the cover to bolt down to the housing metal-to-metal with nothing soft in between to slide around or compress. I am not sure if the T/A cover has this too.
10-02-2005, 02:32 PM
#19
Originally Posted by TXsilverado
so yall are saying that all of my favorite shifts are killing my tranny 
i love that 4-1 shift too doug 
i know its a ticking time bomb every time i do it but i just cant stop 
i love that 4-1 shift too doug i know its a ticking time bomb every time i do it but i just cant stop 
I've done the easy things to strengthen my setup (shiftkit, locker, added fluid capacity) but until I actually get a "Built" tranny AND bullet proof my u-joints/driveshafts/rear end, I have to be real with myself, knowing at some point these things will go south.
but thats the name of the game
10-02-2005, 04:31 PM
#20
cant you weld reenforments on the 10 bolt like ooffroad people do to them . you know what im saying wont thqt help flexing . and im glad i have a 75 k warrenty on my stuff u guys have me stressing out right now bout the next time i do my 30mph pedal to the metal 10 foot burnout marks lol