Uh Ho, Transmission problems? Help!!!!

[BillyGman]

I have 9K on my Marauder, and one night during the Christmas holiday I had a full car load of people in it. Among my 4 passengers that I had in the car that night there was a rather large lady who said, "Lets see what this car can do". So those of you who know me, also know that you don't have to say that to me twice.

So from a 30 MPH coast while in third gear I stomped on the gas pedal and for the first time ever (which BTW was the first time that I ever pegged the gas pedal w/a car load of people) something didn't feel right. The transmission initially downshifted to second gear, but only for for about a half second duration, and then slammed into first gear as the car rocketed forward. And when I say "slammed" I mean I felt something hit like a hammer. This wasn'r a smooth transition at all. It felt like metal to metal hitting together hard w/out any hydraulic fluids involved. It was as if there was a momentary slip, and then when it grabbed, it hit really hard.

Since then, it's now got to a point that whenever I kick down hard on the accelerator from about the same speed(from a 20-30 mph cruise) the same thing happens. It feels like something slips for a split second, and then the car is just pounded into the lower gear w/a resulting shockwave going through the entire drive train!!!!!

I haven't noticed any ill effects w/normal driving, but this has me concerned. I realize that it's difficult for anyone to diagnose any possible mechanical failure via the internet, but I'd like to hear from anyone if they have had a similar experience, and what the specific diagnosis turned out to be.

I'd also like to get some opinions based on peoples' experiences as to weather ir not I should bring the car into my dealer about this, or if I should just wait to see if the problem gets worse, or something goes. the rason for the latter question is that I'm not at all sure if any mechanic would be able to diagnose a problem like this w/out pulling things apart.

[gilby04]

Bill,
My view is,
If your MM is exhibiting poor performance compared to what you've come to expect, visit your dealer in order to document the issue. It appears that the problem is not going to fix itself, and, if delayed any longer, may result in additional or more serious problems...perhaps the solution may be a simple tweak ...better safe than sorry!

[BillyGman]

HMMMM, maybe you're right. Thanks.

[mtnh]

HMMMM, maybe you're right. Thanks.

Bill, that 30 mph region is a tough one on a transmission for a floor slam of the accelerator. It's right on the hairy edge of being ready to leave first gear, but the progamming allows it, and then you get right out of first from the torque rush and resulting close-out of first gear speed range. I would say that it is normal for the transmission to do that, even with the chip in there. That said, I would never try that from 30 mph. If you are doing some exhibition driving, and you are doing around 30 mph or so, do yourself a favor and manually select 2nd with the shifter. While the gas pedal is floored, move the shift up to drive, deselct overdrive, and watch the car shift out of second at whatever Dennis has the limit set to with your geard. Mine, with stock everything, shifts out of 2nd exactly at 90, with a neck snap to some degree. That should be convincing enough for your passengers. :coolman:

Mike

[BillyGman]

Okay. I'm open to all viewpoints on this. i was convinced that it's doing something that it wasn't doing before, but in light of what you've written, now I'm beginning to wonder if perhaps I just never noticed it before. I'll have to deliberately try doing this at different speeds to make a better assessment. Thankyou.

[darebren]

should have tossed the fat lady out first.

[cyclone03]

Billy,
I have to wonder if some of it is the converter too.
Mine seems right at the transition from lock up to open at the same speeds at times.
The extra wieght will also cause the converter to see more load.Slip more.

I'm going to call DR about some shift programming changes as soon as I can document when/where/rpm/speed/gear the strangness happens.

[TripleTransAm]

Slippage = RPM rise (beyond the converter stall speed, of course) with no increase in road speed. If something did get knocked out of whack in your tranny, your wild RPM increase with no forward motion might indicate something slipping wildly until it catches.

When the tranny "downshifts" (or whatever it is doing) try to note the speed and RPM where it happens. Then, try to duplicate that RPM/speed range manually. ie. if at 30 mph the RPM shoots to 5000 RPM when it kicks down to 2nd, try holding 2nd manually until that road speed and see if it correlates. If you are truly slipping, you will see much less than 5000 RPM at that speed in that gear. If you do see the same RPM, then it's just a matter of a violent downshift.

While you're at it you can try standing on it in manual 2nd and see if it slips in the same fashion. At the very least, you can see if your torque converter is misbehaving.

Of course, this last test isn't a 100% accurate test... for example, manual 2nd seems to apply a few more bands and/or clutches than the automatic 2nd gear application. But if anything, you can prove the RPM/speed relationship is true as compared to the automatic downshifting, and if you DO see slippage in manual 2, then something is rotten in Denmark.

[SergntMac]

What's happened to me a few times, sounds like the same thing you describe Billy.

I was cruising a bit faster, locked-up and in OD, maybe 40-45 MPH, and just nailed the gas. In a split second, it unlocked, paauuussed like it was bogging or something, then bam! Into 1st gear and almost at redline, a second later back into 2nd gear and gone.

I didn't hear any unusual sounds, but the downshift brought my azz end around. I was just goofing off all by myself, but if I was taking someone on, they would have got a car length on me in that pause. Now I drop into 2nd before I punch and move it into 3rd after well away from 1st gear territory like TTA explaind.

If you heard some noise other than what you are comfortable with, check it out. But first, put the car on a lift and look for fresh contact around the rear end. With all the additional weight in the car, and the added torque, you may have just bottomed out.

Did they enjoy the show?

[junehhan]

I think i've experienced this "violent downshift" thing some of you guys have described. When I was getting onto the highway one day, I floored the gas pedal at 38mph, and there was a slight pause which actually felt like an eternity, but it downshifted into 1st gear very hard and off I went. I've also experienced a similar thing going like 75mph and flooring it which caused a fairly violent downshift into 2nd gear. I don't know about your case, but I thought my case were perfectly normal and just avoid the situation by making sure I pay attention to what my speed is before flooring the gas.

[Murader03]

I'll throw in my $.02's. With the 4.56's and the Stallion, I think what your getting would be normal. I have 4.10's and when slammed at a low speed, the tranny will jump to low and really snap in and slam you back in the seat. I've done this several times, often by mistake not thinking the tranny would drop back into 1st on the downshift. It really suprises you, but again, I think it's a normal response. There have been times that I tought I was rolling to fast for the downshift to 1st, but it still dropped in there and really slammed home as the revs were already built up. It didn't take long before the upshift came into play. :burnout:

[BillyGman]

hey, you guys are really great! Thanks for all the responses you've written. I think what Murader03 and others have written pretty much explains it. I was playing around w/the car today experimenting a bit, and atleast so far it doesn't seem like any big deal.There is no noise when this occurs either. Perhaps I'm just getting more observant of certain things now that I have put several thousand miles on the car.

BTW, MAC, yes the passengers that I had in the car that night all liked the show BIG TIME. The BIG lady in the back seat yelled out "It just felt like I left my behind back there on the street"

[Marauderjack]

My 2000 CV would do the same thing!! If you really want to think you're tearing it up just get off the gas slightly while it pauses!!!! It will "DOUBLE SLAM" and you will swear you have ruined it!!! :cry:

I have felt something similar in my MM when I went to about 3/4 throttle at about 25 MPH.....I realized it was about the same as the CV!!! :nono:

Take the advice and manually put it in second when you floor it!! That will eliminate the "Bang" to 1st?? :shot:

Marauderjack ;)

[junehhan]

The bang to first gear often has a very desirable effect. It just feels good when the transmission downshifts and you just haul ass away. What I don't like is how the Marauder will allow the tranny to downshift into 1st at such high speeds. IMHO, the Marauder should never downshift to first at 36-38mph because you are almost maxed out in rpms at that speed in 1st gear anyway. My old 00 Crown Vic if I remember correctly, wouldn't downshift to first at WOT if you were going faster than 25 or so.