Wheel hop in a FWD?
Sure it isn't torque steer?
Sure it isn't torque steer?
2000 STS - Is a fast launch even possible?
If I nail the throttle at the lights it feels like the front is hopping up and down. Not good.
At 40mph if I nail it even then it can feel like the front end is hopping.
Is this normal?
I mena, I know it's FWD and plenty powerful, but someone I know ho has one of these said he had no such problems.
Maybe I just drive it harder?
At 40mph if I nail it even then it can feel like the front end is hopping.
Is this normal?
I mena, I know it's FWD and plenty powerful, but someone I know ho has one of these said he had no such problems.
Maybe I just drive it harder?
1 - 20 of 29 Posts
What it is is wheelspin.
It just sounds harsh like the front is hopping (which it may be slightly).
How they get 1/4 mile times of 14.8 seconds I will never know as it's so bad...
It just sounds harsh like the front is hopping (which it may be slightly).
How they get 1/4 mile times of 14.8 seconds I will never know as it's so bad...
Maybe the traction control kicking in?
How is the tread on your tires? Is the ground clean of sand / ice?
If uphill you can certainly feel weight transfer to the rear, and thus a loss of grip.
Check for codes... do a search on the forum on accessing the onboard diagnostics--it will know if something is not working properly.
If uphill you can certainly feel weight transfer to the rear, and thus a loss of grip.
Check for codes... do a search on the forum on accessing the onboard diagnostics--it will know if something is not working properly.
If your air pressure is high (around 35psi or more) the front end on these car can hop a little when the tires brake loose. I ran a 14.809 at Atco Raceway about a month ago. The last run I made, I had 22psi of air in the front tires, and still had traction problems. I know this, because my trap speed was fast enoguh for a 14.7, but my time was slower around 14.849.[email protected] said:What it is is wheelspin.
It just sounds harsh like the front is hopping (which it may be slightly).
How they get 1/4 mile times of 14.8 seconds I will never know as it's so bad...
I'm not sure why the front end would be skipping around at 40+mph though. Maybe you were going slow enough to catch the tail end of first gear on the downshift (1st runs out at about 40-42mph).
Probably a tire problem. my Eldo would loose traction going into second on WOT and torque steer like crazy, after a new set of tires torque steer isn't even noticable and when it shifts into second it just leaps forward
The car is wearing its original Goodyear Eagle Touring tyres.
It's done just over 17,000 miles and they're starting to get low (they'll need replacing by 20,000 miles or so).
The weaher is cold, and during the day there are traces of salt on the roads but it isn't icy or wet.
If I nail it off the line the car moves forward but the wheelspin sounds really nasty (unlike my RWD Camaro) as it puts lots of vibration through the car. It even sounds like the exhaust is hitting something. The traction does not kick in in this situation (although it does work becuase it kicks in when its wet and I do a similar thing).
It does this from a standing start, or a rolling start up to almost 6,000rpmn in 1st, and when it shifts to 2nd it does it a bit then too.
I'm starting to baby it up to 40mph now as I don't want to break anything!
It's done just over 17,000 miles and they're starting to get low (they'll need replacing by 20,000 miles or so).
The weaher is cold, and during the day there are traces of salt on the roads but it isn't icy or wet.
If I nail it off the line the car moves forward but the wheelspin sounds really nasty (unlike my RWD Camaro) as it puts lots of vibration through the car. It even sounds like the exhaust is hitting something. The traction does not kick in in this situation (although it does work becuase it kicks in when its wet and I do a similar thing).
It does this from a standing start, or a rolling start up to almost 6,000rpmn in 1st, and when it shifts to 2nd it does it a bit then too.
I'm starting to baby it up to 40mph now as I don't want to break anything!
The cold weather can do it to. It was 24 degrees outside, when I went to drive over to my friends house. I was doign aboru 25mph or so, when I punched the gas to merge onto the highway (it was 11:00 at nightm, and not many people on the road). When I hit the gas, it downshifted, and I could tell that the wheels were spinning like mad, because I lost all control of my steering. They kept spinning until about 65mph, when I got toawrds the top of second gear. The car had downshifted into first which was why the tires broke loose, alogn with the very cold weather.
I wouldn't be worried abotu breaking anything, unless the vibration is enough, to cause the car to drift into a pole or something.
As caddypete mentioned, it could be a tire issue as well. They may just be struggling for grip, causing a bid of wheel hop. After you get some new tires, give it another go, and see if it makes any difference. These cars do like tires with lots of grips. I've got Toyo Proxes on mine, and usually don't get a whole lot of hop, or wheel spin (unless it's cold outside).
I wouldn't be worried abotu breaking anything, unless the vibration is enough, to cause the car to drift into a pole or something.
As caddypete mentioned, it could be a tire issue as well. They may just be struggling for grip, causing a bid of wheel hop. After you get some new tires, give it another go, and see if it makes any difference. These cars do like tires with lots of grips. I've got Toyo Proxes on mine, and usually don't get a whole lot of hop, or wheel spin (unless it's cold outside).
Yeah I'll fit Toyo Proxes, they're my favourite tyre.
Some of what you are describing sounds like a problem I had with my 90. It had a broken motor mount. On a front wheel drive car the torque on the mounts is monster. You can see too much flex by having someone holds their foot tight on the brakes and tap the gas just enough to make the car rock against the brakes. If you have a broken mount the engine will jump or dive depending on which mount is broken.
There's your problem! Those original Goodyear tires are very hard and not sticky! I went to a 255mm Z-rated tire, and it's much harder to loose traction! 
I don’t know if it’s just psychological but I find my 2001 RHD gets away quicker in 2 than in D.
I'll have to try the 2nd gear start in my 2003 STS and use a stopwatch to see what's happening....
Well, technically it is a tiny bit faster, ubt only by a few thousanths of a second at most. This is because the line pressure in the transmission in raised resulting in a quicker and firmer 1-2 shift. Other that that, your still just running through the gears liek you would at WOT in D. You're never going to be able to tell the difference with a stop watch. I would also suggest holding onto the wheel, because the front tires have a tendency to break loose when the car shifts into 2nd gear. It always lets out a loud bark form the tires....usually suprises a few people.
On some transmissions, line pressure would indeed cause the "shift," but once upon a time I asked our "old friend Bob" and his comment was along the lines of line pressure not being responsible for the shift, but rather the algorhythm in the E-transaxle.danbuc said:Well, technically it is a tiny bit faster, ubt only by a few thousanths of a second at most. This is because the line pressure in the transmission in raised resulting in a quicker and firmer 1-2 shift. Other that that, your still just running through the gears liek you would at WOT in D. You're never going to be able to tell the difference with a stop watch. I would also suggest holding onto the wheel, because the front tires have a tendency to break loose when the car shifts into 2nd gear. It always lets out a loud bark form the tires....usually suprises a few people.
From personal experience, while doing the maintenance "carbon cleaning" in 2nd gear, and letting the revs get high enough for the transmission to go into a protective shift into 3rd, indeed the tires chirped.
When just doing WOT in D, tires do not chirp at the shift point (still @ ~6500 RPM). The hard shift may actually better for the transmission than the smooth shifts too... something having to do with clutch plates.. but beyond the scope of my post, or full understanding.
The line pressure is the fluid pressure acting upon the clutch plates. This fluid pressure is what actually shifts the transmission (i.e. forcing clutch and steel plates together, causing them to hold a rotating helical gear set inside the trans, resulting in a change in ratio). The algorithm is just the programming designed into the transmission that determines things such as how long to hold a gear for, atw hat rpm to shift at,...ect by controlling the valve that direct the fluid and pressure mentioned above.
By selecting 2nd gear, you indirectly increase the fluid pressure acting upon the clutch packs inside the tranny. This is what give you that crisp, quick shift that chirps the tires. Since it is faster, and more forceful, it results in less slipping between clutch, and steel plates whcih is better for the transmission. The only downside to this is the shock to the rest of the drivetrain. While it's not enough to cause any real damage if doen every once and a while, doing so at everystop light would certainly break something. That's why I only do it ocasionally.
By selecting 2nd gear, you indirectly increase the fluid pressure acting upon the clutch packs inside the tranny. This is what give you that crisp, quick shift that chirps the tires. Since it is faster, and more forceful, it results in less slipping between clutch, and steel plates whcih is better for the transmission. The only downside to this is the shock to the rest of the drivetrain. While it's not enough to cause any real damage if doen every once and a while, doing so at everystop light would certainly break something. That's why I only do it ocasionally.
I know what you mean. I wish I could find Bob's quote, but I didn't save it in my e-mail. He said something along the lines of "the 4t80-e is so complex that it is impossible to explain here. Line pressure is not making any of your shifts."
My original question was an elaboration on whether the transmission or the PCM was making the decisions as to what gear to use when, and someone brought up shifting "hard" via line pressure. Someone else said hard shifts are sometimes better than the smooth ones, due to less constant friction in the clutch plates or something like that. The above "quote" was his response, and the thread ended there. Of course it's been deleted since, along with the rest of the goldmine.
He made it seem like the 4T80-E is not your ordinary transaxle, and is much more sophisticated than anything before it, by a long shot.
My original question was an elaboration on whether the transmission or the PCM was making the decisions as to what gear to use when, and someone brought up shifting "hard" via line pressure. Someone else said hard shifts are sometimes better than the smooth ones, due to less constant friction in the clutch plates or something like that. The above "quote" was his response, and the thread ended there. Of course it's been deleted since, along with the rest of the goldmine.
He made it seem like the 4T80-E is not your ordinary transaxle, and is much more sophisticated than anything before it, by a long shot.
Ok danbuc, I found the original posting. Unfortunately Bob's post is gone from it. :helpless:
http://www.cadillacforums.com/forums/showthread.php?t=45267
Not surprisingly, you were very helpful, thoughtful, and informative, as usual. An asset on the forum, "fo sha." :thumbsup:
http://www.cadillacforums.com/forums/showthread.php?t=45267
Not surprisingly, you were very helpful, thoughtful, and informative, as usual. An asset on the forum, "fo sha." :thumbsup:
Ok, unless your car was sliding around corners all day long, how the hell are the tires shot at 20k miles?????????????????????
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