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TCC lockup or not?

orrum

orrum

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Location
Orrum North Carolina
I tow a lot and in searching the threads I have run into different opinions about thr TCC lockup mod on my truck. Some feel that my tranny cant stand the abuse from locking up the tranny. What have yall that have the mod experienced with its use? If u tow? Also my truck has overdrive with the 4l80e tranny, would putting the shift lever in 3rd do the same thing and lockup the tranny like the tcc mod?
 
I have the TCC manual lockup on my 4L80E, but haven't used it much yet for towing. I've played around a lot with it empty and like the compression braking it gives.

I'll be having a chance to try it while towing this coming weekend. That should be a good test as we're planning to go over Santiam Pass in the Cascade mountains, ending up in the Metolious (meh-tow-lee-us) River area. We're at just over 200 foot elevation at home and the pass is 4817 ft in elevation. There are several stiff grades to go over in around 100 miles to the Metolious area. The last 5-6 miles on the west side of the summit climb about 1000 ft, and the five mile long descent on the east side drops about 1500 ft.

Here are some web sites about the area that give details and pics.

http://en.wikipedia.org/wiki/Santiam_Pass

http://shokai.blogspot.com/2009/02/santiam-pass.html

http://en.wikipedia.org/wiki/Metolius_River

I know this is way too far for the travels you are planning for this summer, but, if you ever get a chance to get out to Oregon the Central Oregon area is a must see place. Santiam Pass, the town of Sisters (tourist trap with a western theme), Metolious River, Mt Jefferson, Three Finger Jack, the Three Sisters, Broken Top (all are volcanic origin), Century Drive and all its' lakes, and many other places.

Enough of the hijack, back to your question.

Don
 
The 4L80E does a good job with the lock on down grades or to decelerate. The problem is more from locking it up during shifts. Violent downshifts will wear it if locked and potentially break it. The stock program unlocks when down or up shifting. And also probably best to not have it on in second gear, because theres more torque transferred when it downshifts to 2nd or 1st making that potential issue worse. Having it controlled by the computer would make it safer allowing it to unlock on downshifts. It If you keep it on only at speeds above 50mph then there would be less chance of issues.
 
Hey Don I am going for three months, I might make it to ur area. Thanks for hijack info. So Buddy and u others why cant I get the sam effect by manually shifting it to third? Would me shifting it slow me down and thennot slow me because it would kick out of tcc lockup and freewheel? I want it to go down mtns morethan climb them. My load is gonna be fairly light, 1000 trailer with only 150 gallon of veggie oil by the time I hit serious mountains, my camper is a very light weight one, probably less than a 1000 lbs. I will weigh it when I get it loaded. The trailer does not have brakes, old school lil bitty two horse trailer. Can add them but dont wsnt to. I pulled a similar trailer with two horses in it in Pa with a half ton Ford with a 300 six cylinder gas motor. Went all in them mountains with no problem for years. Explain the third gear thing workings plz.
 
Third gear without lockup will only provide a very slight amount of resistance. Nothing that will help you on a real grade or with a trailer. The engine will merely drop down to idle RPM and coast. TCC lock in third is very effective going down a grade, even OD lockup down a grade is usually good enough to keep you from accelerating when empty.
 
Ok Buddy now I am clear about how each method works. Just not sure what to do, guess I will stay up on the fence for a little longer. Really want several of yall to be the guinea pigs. I got a while before I hit them wedstern mtns and I can do the mod on thetrip if I wsnt.
 
I use the PCM to keep mine locked on deceleration, it was an option GM had available in the programs but opted not to do it. A lot of other people with 94+ trucks and aftermarket programming have the same setting to help when towing. With the PCM setting it still unlocks as soon as you hit the brakes, whereas an override switch could keep it locked while braking.
 
Well if anyone is going to tear it up towing it would be me.
The first thing to burn up is the small over run clutches in the trans that are used with manual 3rd, 2nd etc. I burnt up 2nd gear manual compression braking about 25K miles after a fresh rebuild.
At 50K the torque converter was slipping. Trans needed a rebuild at this point.
Pan drop, oil was changed at 25K.

The computer does TCC lock at WOT after awhile. Compression braking is the weak link. So is the TCC clutch.

Do not lock the TCC clutch on compression braking. There isn't much of a lockup clutch in manual second. Power from engine through the overrun roller clutch is not affected by this in 2nd gear.

Least I can serve as a bad example.
 
U go Warwagon! So where r u in Az? I want to see the Navaho Nation and find some old timer to show me their rug, blanket making and dyeing. Want to see the quaking aspen high country places that Zane Grey wrote about.
 
you need to go up in the mountains in southern Utah. lots of quakies I've seen some with dates carved in them back to the 1800s
 
Hey thanks Ak going to Utah for sure. Gotta see Pail, Paulotivitz, probable spelled that wrong. That sounds like what I want to see. Going to see a mechanic to get the ac fixed today, cross fingers, pray a little, gonna have more in the ac money wise directly than I paid for the truck! LOL
 
handcannon said:
I have the TCC manual lockup on my 4L80E, but haven't used it much yet for towing. I've played around a lot with it empty and like the compression braking it gives.

I'll be having a chance to try it while towing this coming weekend. That should be a good test as we're planning to go over Santiam Pass in the Cascade mountains, ending up in the Metolious (meh-tow-lee-us) River area. We're at just over 200 foot elevation at home and the pass is 4817 ft in elevation. There are several stiff grades to go over in around 100 miles to the Metolious area. The last 5-6 miles on the west side of the summit climb about 1000 ft, and the five mile long descent on the east side drops about 1500 ft.

Here are some web sites about the area that give details and pics.

http://en.wikipedia.org/wiki/Santiam_Pass

http://shokai.blogspot.com/2009/02/santiam-pass.html

http://en.wikipedia.org/wiki/Metolius_River

I know this is way too far for the travels you are planning for this summer, but, if you ever get a chance to get out to Oregon the Central Oregon area is a must see place. Santiam Pass, the town of Sisters (tourist trap with a western theme), Metolious River, Mt Jefferson, Three Finger Jack, the Three Sisters, Broken Top (all are volcanic origin), Century Drive and all its' lakes, and many other places.

Enough of the hijack, back to your question.

Don
Click to expand...

Beautiful. I hope you're bringing some fly rods.
 
handcannon said:
I have the TCC manual lockup on my 4L80E, but haven't used it much yet for towing. I've played around a lot with it empty and like the compression braking it gives.

I'll be having a chance to try it while towing this coming weekend. That should be a good test as we're planning to go over Santiam Pass in the Cascade mountains, ending up in the Metolious (meh-tow-lee-us) River area. We're at just over 200 foot elevation at home and the pass is 4817 ft in elevation. There are several stiff grades to go over in around 100 miles to the Metolious area. The last 5-6 miles on the west side of the summit climb about 1000 ft, and the five mile long descent on the east side drops about 1500 ft.

Here are some web sites about the area that give details and pics.

http://en.wikipedia.org/wiki/Santiam_Pass

http://shokai.blogspot.com/2009/02/santiam-pass.html

http://en.wikipedia.org/wiki/Metolius_River

I know this is way too far for the travels you are planning for this summer, but, if you ever get a chance to get out to Oregon the Central Oregon area is a must see place. Santiam Pass, the town of Sisters (tourist trap with a western theme), Metolious River, Mt Jefferson, Three Finger Jack, the Three Sisters, Broken Top (all are volcanic origin), Century Drive and all its' lakes, and many other places.

Enough of the hijack, back to your question.

Don
Click to expand...

Beautiful. I hope you're bringing some fly rods.
 
I can show you the 6.5 killer mountain grade! :hihi:

titan missile museum
www.titanmissilemuseum.org/

Or a hole in the ground
Grand Canyon

It is already over 100 degrees out here now. Ya sure? :eek:
 
Well I for one r trying to get the ac to work but if not I am still gonna saddle up n ride! Yee haw cowboy up theres a world out there for me to see!
 
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