PCM tuning & Torque Management= weak driveline?

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Old 07-15-2005, 06:40 PM
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Default PCM tuning & Torque Management= weak driveline?

I'll be the first to admit that I don't know much about computers, the one I'm typing on now or the ones controlling modern day vehicles. However, it seems to me that with the computer controlling EVERYTHING in vehicles now adays, the manufactures can make a cheaper product. Alot of people dog the Hemi engine because the Hemi Ram doesn't dyno very good numbers. We've all seen the commercials, a Hemi Ram smoking the tires through the intersection somewhere. Then why doesn't mine smoke them like that too? DC tuning, that's why!! I do think the Hemi is a 345 hp engine, DC just doesn't allow alot of that to get to the rear tires. They want to protect the transmission and rearend! Since they can control how much power goes through the driveline with TM, then they can make a weaker transmission and rearend, and still advertise the 345hp HEMI engine. Since they offer a 7/70 warranty, they TM the hell out of the truck so they won't have to replace a trans at 69K miles. I'm sure others do this too, it's not just DC. The TM let's them put in a weaker product because they control actually how much power they'll allow through the driveline. Am I way of base here or what?
Jim
Old 07-15-2005, 06:59 PM
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You about summed it up pretty good..............
Old 07-15-2005, 08:49 PM
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hit the hail on the nead!
Old 07-15-2005, 09:35 PM
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It would be hard to disagree with any of those statements, however I do not think the rearend in our trucks are weak by any means, They are not as strong as the 9 3/4 Dana 60 but the 9 1/4 does not require the 75 HP it take to push the Dana 60 either. I would be willing to be the 9 1/4 is stronger than the 8 3/4 of which I had several that I put thru Hel... and they were bulletproof. We being on the net these days here a lot about problems but if we were to disregard anything we have heard online, How many problems do you know about directly? Most of the rear end problems I have heard about ( including the web ) are from those people who have changed gear sets, for whatever reason. Now I am not saying there are not some who have had problems with their stock setup, I am sure that happens with ALL makes.
the Trans for me is the big unkown, being of a Mercedes design I am unfamilar with them, All I do know is a handful of people on here have been using a bunch of N20 and Drag Radials with no problems. I am using a small shot and Nitto Drag Radials( Off the line ) and that is a pretty good test of rear ends and trans.... will be using a larger shot soon..
Just my 2 cents
TJ
Old 07-15-2005, 10:21 PM
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Well, I have had a probelm with my rearend and I will admit, I probably did it. I've done more than one dead stop, punch the gas burn outs or tried so that's probably what did it. My mechanic found about 3-4 broken teeth on gears in the carrier assmebly in my rear end when I had the 15K check done, the dealer replaced them with question which was nice. Other than that, no, I haven't had any problems. I'm not ******* DC, it'S just something I've been wondering about more than I have actual proof.
Jim
Old 07-17-2005, 09:20 PM
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Originally Posted by Ram4Pick
Well, I have had a probelm with my rearend and I will admit, I probably did it. I've done more than one dead stop, punch the gas burn outs or tried so that's probably what did it. My mechanic found about 3-4 broken teeth on gears in the carrier assmebly in my rear end when I had the 15K check done, the dealer replaced them with question which was nice. Other than that, no, I haven't had any problems. I'm not ******* DC, it'S just something I've been wondering about more than I have actual proof.
Jim
Hmm sorry to hear that, I have about oh somewhere around 300 or so Dragstrip launches, at least half of them are powerbraked to at least 1000rpm to 2000 Rpm, Countless full bore burnouts and about 15 N2O launches from the line ( 35 to 50 shot so far ) on the Nitto Drag Radials..... I do not baby my truck in the slightest.
I am just wondering, what did the pattern on the teeth look like? was there evidence of excessive backlash? Infrequently there may be just a tiny stress crack in the gear that causes the problem ( I have seen this in broken axles, a manufacturing defect ) and it would not be a far stretch to see it happening in the gearsets.
I Personally will not be worried about putting 500 HP to the rear with a automatic.
What solution for repair did you use and have you had problems since?

TJ
Old 07-17-2005, 09:37 PM
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Originally Posted by MrDestinE
Hmm sorry to hear that, I have about oh somewhere around 300 or so Dragstrip launches, at least half of them are powerbraked to at least 1000rpm to 2000 Rpm, Countless full bore burnouts and about 15 N2O launches from the line ( 35 to 50 shot so far ) on the Nitto Drag Radials..... I do not baby my truck in the slightest.
I am just wondering, what did the pattern on the teeth look like? was there evidence of excessive backlash? Infrequently there may be just a tiny stress crack in the gear that causes the problem ( I have seen this in broken axles, a manufacturing defect ) and it would not be a far stretch to see it happening in the gearsets.
I Personally will not be worried about putting 500 HP to the rear with a automatic.
What solution for repair did you use and have you had problems since?

TJ
I'm not a gear expert or even that familiar with them so I really couldn't tell what caused it. Different causes may look different to someone who really knows but the top half of four teeth were gone, there were a bunch of little pieces in the pumpkin. The funny thing is, I have no idea when or which burnout out it could have happened on. The rear end didn't feel funny, make any noise at all, I was kind of shocked when I saw it. I could have just gotten a defective gear, who knows?
Jim
Old 07-18-2005, 06:48 PM
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Well I suppose that if the tips just cracked and fell off you would possibly never hear it or even know it when it happended..... You would have definately known it if a piece had gone between the gears.... dam don't see any boom smileys! ;-) Hope that particular trouble is behind you for good.


TJ
Old 07-18-2005, 07:51 PM
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I also have to say I had to get my rear end rebuilt after 20K, was getting a check up on it replacing the fluid, they pulled the cover off to find all the posi clips laying in the bottom. Truck was still driving just fine but it had to be rebuilt.

A coworker got a rc/sb ram, built on the same day as mine, came in on the truck the same day. He had a drone in his rear end at 45mph, the week before I took mine in he had his rebuilt too, got 3mpg better out of the deal too. No idea what was the specific problem with it.

I am not worried about the full thottle shifts on the tranny with the wire pulled but the rear seems to be a little weak in my opinion. Before I goto slicks I am going to try and snag the 4:10 dana rear end out of the srt-10, I'd put money on my rear end breaking before anything else.
Old 07-19-2005, 09:13 PM
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Originally Posted by Toe
I also have to say I had to get my rear end rebuilt after 20K, was getting a check up on it replacing the fluid, they pulled the cover off to find all the posi clips laying in the bottom. Truck was still driving just fine but it had to be rebuilt.

A coworker got a rc/sb ram, built on the same day as mine, came in on the truck the same day. He had a drone in his rear end at 45mph, the week before I took mine in he had his rebuilt too, got 3mpg better out of the deal too. No idea what was the specific problem with it.

I am not worried about the full thottle shifts on the tranny with the wire pulled but the rear seems to be a little weak in my opinion. Before I goto slicks I am going to try and snag the 4:10 dana rear end out of the srt-10, I'd put money on my rear end breaking before anything else.
Well, I am on 305/55R/18 Nitto Drag Radials now ( am not yet shaving the Calipers to run 16" Hoosiers but that may happen ) and I intend on putting at least ( if I can hook it up ) 125 shot on it off the line.... I will keep you all posted!

TJ


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