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2000 Seville SLS
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16 Posts
Discussion Starter #1
My wife and I took a trip into the mountains this weekend. Denver to Rifle, that means going thru the Eisenhower Tunnel and over Vail pass.
For the worst of both passes, I locked the tranny in 2nd and kept the engine at about 4000 rpm.
Good for the rings, right? (my average MPG is up 2 since the trip)
Temp rose to the 1/8 to 1/4 mark right of center during these passes. Stays centered otherwise.
For those who haven't pulled these two hills:
Eisenhower climbs to 11,013, the grade is 7 percent on the west approach and 6 percent on the east approach.
Vail pass climbs to 10,500 or so and isn't quite as steep.

Sunday on the way home traffic on the east side of the tunnel was terrible, lots of time in 1st and second, but the shifts to second started banging under really light throttle. Ambient air temp was around 85 degrees.
It would occasionally thump into second but this was a substantial BANG, like a manual 1-2 shift at high rpm.
I think that the front mount is broken, but it has never exibited this level of harshness before.
Nothing like this before and it seems fine today.

Thinking about it, this may have been caused by light loading of the mounts from the grade and light throttle input allowing things to flop around a bit more than normal.

Am I on the right track? Any ideas?

No codes except a lost comm to the PCM and one for a refrigerant overpressure.
I unplugged the PCM to reroute the harness for easier access to the Tranny dipstick.

2000 Seville SLS
 

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Registered
2000 Seville SLS
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16 Posts
Discussion Starter #3
I will still occasionally thump into second gear but nothing like what was happening on Sunday.

Sometimes it almost feels almost like it is between gears. Like coming off of a corner I have to really nail it to get it to accelerate and it downshifts. Or an off on throttle input will really mess with it. Slowing for a light drop the gas, it changes, hit it and blaaaaaaaaaaaaa nothing. Toss out the anchor. If I let off and then hit it again it will go.
Either of those don't happen often.

Bad TPS maybe, but wouldn't that set a code?

The engine rocks significantly when going from reverse to drive.

Fluid looks and smells fine, I plan on changing to full synthetic this weekend.

I just turned 75k.
 

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2008 SRX
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403 Posts
???????? !
Not much to check short of hooking the Tech-2 up and going for a drive. There's alot in the data list that will tell what's happening. Maybe a sticking valve in the valve body.
 
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I have had a hell of a time with hard shifts and other tranny issues and in the end I replaced the PCM and my car is now a mean screaming and smooth machine.
 
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