Has anyone else noticed a tendancy for the car to kind of buck a little at slow speeds/low rpm? Sometimes, while in first lets say, if you let off of the gas it tends to buck a little and you can hear the clank from the back end as the drive train moves. Sorry but this is the only way I can describe it. My 01 GTS had a little of the clanking sound from the rear end like this but the SRT10 has more. If you get on the gas it immediatley smooths out. Has anybody else noticed this or understand what I am experiancing?
Question on SRT-10 Drivetrain Slack
- Thread starter fred
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Paul Hawker
Enthusiast
My 03 bucks a little at low throttle settings, and at low speeds, but MUCH less than my 96. No rear end clank here. Over all driveline seems much smoother, and more precise.
Viperfreak2
Enthusiast
I have the buck-n-clunk....dealers say it 'normal' for cars with such high horsepower. Right. Tell that to the Mercedes guys with 600+ ponies.
Here's what PVO has to say
Question 11:
First of all, I LOVE this new machine! Here's the observation, and I'm wondering if others have experienced this. Second, third and fourth gears at "coasting" speeds, semi-gentle quick stabs at the go pedal are producing HUGE amounts of backlash-sounding driveshaft and differential noise, much like used up GM muscle cars or a 12-year-old 928S4. Any comments?
Answer 11:
The noise you are describing is normal. What you hear is the driveline backlash that occurs as a result of the significant levels of torque being managed by the driveline. This noise is normal.
Question 11:
First of all, I LOVE this new machine! Here's the observation, and I'm wondering if others have experienced this. Second, third and fourth gears at "coasting" speeds, semi-gentle quick stabs at the go pedal are producing HUGE amounts of backlash-sounding driveshaft and differential noise, much like used up GM muscle cars or a 12-year-old 928S4. Any comments?
Answer 11:
The noise you are describing is normal. What you hear is the driveline backlash that occurs as a result of the significant levels of torque being managed by the driveline. This noise is normal.
Skip White
Enthusiast
This is very much the nature of the car. It seems as time goes you get better at handling this. When your loafing around in the parking lot you have to be on the throtle or completly off. Sometimes you just have to go in on the clutch and back out.
Skip White
Skip White
Skip White
Enthusiast
Don't forget the Vipers use a very short aluminum driveshaft, that is more sensitive to backlash do to it's lightweight, and the rearend is only two feet away from where your siting in the car, not to mention the monster trany in the car thats right next to you in the car. These factors seem to magnify this affect.
Yes the high HP MB, and BMW's won't do this, because they will spend much on not having the car do this. I will say the Germans now address such things, but who can forget the past MB's with there horrible shifting trans, and noisy valve trains, and timing chains.. Seems like it took them for ever to build a decent transmission and engine.
Skip
Yes the high HP MB, and BMW's won't do this, because they will spend much on not having the car do this. I will say the Germans now address such things, but who can forget the past MB's with there horrible shifting trans, and noisy valve trains, and timing chains.. Seems like it took them for ever to build a decent transmission and engine.
Skip
Paul Hawker
Enthusiast
Most high HP Mercedes use automatic transmissions, which dappens out much of the backlash.
Roadrunner
Viper Owner
- Joined
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Hmmm...
Exactly what 600hp BMW are you referring too... the BMW Williams F1? It runs a 10 cylinder of about 3liters, and I betcha at low speeds it clunks as it probably has no flywheel, just a little muliplate clutch. The badest production Bimmer is that 760iL with a whopping 438hp and no manual trans...
As for MB (the other house of DaimlerChrysler) yeah, the SLR is huge at 617hp. But again, no manual, and it has electronic throttle control to handle such a beast (as many drivers feet cannot). As for AMG, they don't have a single car with over 500hp, and the ones that come close are not naturally aspirated, and thus have way less power at low speeds and low throttle inputs.
Has anyone driven the CLK-GTR (650hp V-12 Naturally Aspirated and only 2200lbs)? Well it's lightweight flywheel induces the same effect you are feeling in your SRT10. The Porsche Carrera GT has an exceptionally light flywheel too... just read the recent articles. Further, drive an SRT10 with a lightened flywheel, the "Bull-Hunch" effect increases dramatically, but the explosive nature of the acceleration is well worth training your foot to apply smooth fuel at low speeds.
Or simply use say 4th gear at about 1000rpm for pooching around town. (Or use that snake oil hammer with reckless abandon)
If you want to eliminate this effect get a heavier flywheel (or an automatic with it's fluid coupling). You could even try a less aggressive throttle plate cam so you'd have to push the pedal more to increase power, and make it less susceptible to the hunching.
Exactly what 600hp BMW are you referring too... the BMW Williams F1? It runs a 10 cylinder of about 3liters, and I betcha at low speeds it clunks as it probably has no flywheel, just a little muliplate clutch. The badest production Bimmer is that 760iL with a whopping 438hp and no manual trans...
As for MB (the other house of DaimlerChrysler) yeah, the SLR is huge at 617hp. But again, no manual, and it has electronic throttle control to handle such a beast (as many drivers feet cannot). As for AMG, they don't have a single car with over 500hp, and the ones that come close are not naturally aspirated, and thus have way less power at low speeds and low throttle inputs.
Has anyone driven the CLK-GTR (650hp V-12 Naturally Aspirated and only 2200lbs)? Well it's lightweight flywheel induces the same effect you are feeling in your SRT10. The Porsche Carrera GT has an exceptionally light flywheel too... just read the recent articles. Further, drive an SRT10 with a lightened flywheel, the "Bull-Hunch" effect increases dramatically, but the explosive nature of the acceleration is well worth training your foot to apply smooth fuel at low speeds.
Or simply use say 4th gear at about 1000rpm for pooching around town. (Or use that snake oil hammer with reckless abandon)
If you want to eliminate this effect get a heavier flywheel (or an automatic with it's fluid coupling). You could even try a less aggressive throttle plate cam so you'd have to push the pedal more to increase power, and make it less susceptible to the hunching.
If you want to eliminate this effect get a heavier flywheel (or an automatic with it's fluid coupling). You could even try a less aggressive throttle plate cam so you'd have to push the pedal more to increase power, and make it less susceptible to the hunching
Why does not Dodge do the above? Are they not interested in eliminating the lurch? I do not mean Dodge should put an Automatic in but why not a heavier flywheel? Is there more to this that I am seeing?
Why does not Dodge do the above? Are they not interested in eliminating the lurch? I do not mean Dodge should put an Automatic in but why not a heavier flywheel? Is there more to this that I am seeing?
Skip White
Enthusiast
Heavy flywheel. The one in the car is unbelievably heavy now. You really do get to where you know how to control the car when it does this. Go in on the clutch and come back out, accel. a little bit, bringing up your speed a few miles per hour, then let off, to a coast. It's at idle speed that the car does this. Fan the engine up and clear it out, this helps You have to be above or below the idle when loping about, and when you can't do the above, just go in on the clutch till you slow down enough. As for a heavier flywheel, this would be very ******* the crank shaft, being the one on the car is so heavy, not to mention the giant clutch, and pressure plate. Drag on engine power would also be terrible.
You really will get used to doing this. It sort of comes to ya.
Skip W.
You really will get used to doing this. It sort of comes to ya.
Skip W.
Viperfreak2
Enthusiast
The large Mercedes coupes and SL65's have 600+ hp. So it's not just the SLR. Yes I agree that the automatics have a rubber band effect on driveline backlash, but even under enormous loads, there doesn't appear to be any slack in the parts. Would a carbon fiber or steel driveshaft fix the clunk in my snake? I would pay a 20 lb penalty if so. I didn't say anything about beamers, but while on the subject....the new M5 is 'reported' to have a 500hp V-10 with a 6 speed manual as one of the trannys. I'll let you know if I need to feather the clutch to avoid embarrassing myself coasting through the parking lot. I'm not a gambler, but I'd bet plenty I won't have to. Other hi-po clunkers? 911 turbo XD50? Lambo Murcielago? Saleen S7? Ferrari F50, Enzo? Z06 Vette? Sorry! had to sneak that one in there! Just to make the argument more interesting.
Paul Hawker
Enthusiast
No reason to argue. The car is what it is. A kick butt, ********* American sports car. Hard riding, great handling, loud, somewhat obnoxious American road speed machine. Anyone looking for anything else should pony up the megabucks, and step up to the plate for a higher end car.
Our beloved Vipers have carved out a niche, which fits us just fine. We can adapt, and if necessary, even put in our own clutches to avoid driveline lash.
The high torque levels, just off idle, is what we all love. That there is no need to rev the car is part of the allure.
Our beloved Vipers have carved out a niche, which fits us just fine. We can adapt, and if necessary, even put in our own clutches to avoid driveline lash.
The high torque levels, just off idle, is what we all love. That there is no need to rev the car is part of the allure.
Hans Christian
Enthusiast
ditto paul
Skip White
Enthusiast
As Paul said, the car is what it is, and like I said, MB and BMW may not do this, but it is at the cost of performance and much money. Upgrades are simple and cheap compared to some cars.
Let the aluminum driveshaft be. Steel would have a terrible drag.
Skip
Let the aluminum driveshaft be. Steel would have a terrible drag.
Skip
Viperfreak2
Enthusiast
I wasn't intentionally trying to compare the Viper to the German Zupercars, just wanting to know if 500+ hp meant that there is no way to eliminate the slack. I love the raw nature of the snake. If it rode harder to improve the handling, great. If it needs the lightweight drivetrain parts to go faster, perfect. My question is: is it really normal, and do we all have the same level of slack? It could be parts quality variation or a design flaw. I guess the only way to compare would be to get a few SRT's together. My opinion is that after a ride in my car, quite a few people would step out saying 'somethin aint right'. I am not one to accept the dealer saying 'normal, go away'. I also won't ask them to fix it, because I'm willing to spend money to make it better. Can anyone tell me the actual cause? Is it the universals on the driveshaft? My GTS and RT-10 had a clunk, but it was different. It would make the noise on hard shifts. A re-torque of the parts fixed the GTS. The SRT is completely different, as described above.
Skip White
Enthusiast
The Diff could be set to loose. As you said, it would be a good idea to drive another SRT, and let another SRT owner drive yours. There may be something there. Your right about the dealer, none of the Viper Techs know what they shoud feel like, they don't own one in most cases.
Skip
Skip
Skip White
Enthusiast
I think it was Pauls car that had a rearend problem, but I don't think it happend at a modest pace. There is a cross pin in the SRT diff. that is very weak, and under load can break.
Skip
Skip
Skip White
Enthusiast
Re: Question on SRT-10 Drivetrain Slack
Yes Fred, the pin is a problem. If it breaks, the pin will tear up the whole rearend. Warranty will fix it, but your car is down for some time. Call Jerry at Unitrax gears. He has made a pin that is very strong. I will be putting one in mine, in the days ahead.
We all get on it every now and then, so it would be a good idea to do this
Skip
Yes Fred, the pin is a problem. If it breaks, the pin will tear up the whole rearend. Warranty will fix it, but your car is down for some time. Call Jerry at Unitrax gears. He has made a pin that is very strong. I will be putting one in mine, in the days ahead.
We all get on it every now and then, so it would be a good idea to do this
Skip
Viperfreak2
Enthusiast
Re: Question on SRT-10 Drivetrain Slack
I was wrong. Today I got the latest issue of Motor Trend with an article on the CL65 AMG. 612 horsepower and 737 lb-ft of torque. Guess what they noticed? "sometimes you'll hear a slight thump from the differential".
All of a sudden, 520 lb-ft doesn't sound so impressive. If they ever put this engine in a lightweight sports car chassis.....
I was wrong. Today I got the latest issue of Motor Trend with an article on the CL65 AMG. 612 horsepower and 737 lb-ft of torque. Guess what they noticed? "sometimes you'll hear a slight thump from the differential".
All of a sudden, 520 lb-ft doesn't sound so impressive. If they ever put this engine in a lightweight sports car chassis.....
drdaveSRT
Enthusiast
Re: Question on SRT-10 Drivetrain Slack
Fred, had the same experience, more with rt, in 25mph zones and below. Cost of doing business.
Fred, had the same experience, more with rt, in 25mph zones and below. Cost of doing business.
fe155
Enthusiast
Re: Question on SRT-10 Drivetrain Slack
When i purchased my 02 GTS with 800 miles the rear clunked and drove me crazy .
i had 150 hp cars years ago that clunked and that was because the ring and pinion were worn or the backlash settings not right. At 4000 miles i switched to 3.45 gears and also have a supercharger and the clunk is gone.I think Unitrax does a better job of dialing in the gears than chrysler.
When i purchased my 02 GTS with 800 miles the rear clunked and drove me crazy .
i had 150 hp cars years ago that clunked and that was because the ring and pinion were worn or the backlash settings not right. At 4000 miles i switched to 3.45 gears and also have a supercharger and the clunk is gone.I think Unitrax does a better job of dialing in the gears than chrysler.
