So I live in a city, and I drive 50% highway, 40% city and 10% suburbs. When Im driving around town, I am constantly battling with Massholes (overly-aggresive Massachusetts drivers). I like to use the J-Gate and keep it mostly in 3rd cruising around 2000-2500 RPM's (sometimes high 2000's), approx 40MPH. I like how the engine slows the STR down like a standard vehicle and conversly love the ability to unleash tremendous amounts of power right in the middle of the power band to avoid these said Massholes and/or get in front of them.

One question: Is this harmful to the vehicle?

 

Probably not harmful to the transmission, but bad on gas millage.

 

Decreased gas mileage would be the only impact I would see also. I usually use the J-Gate in traffic to keep the rpms up a reasonable amount to avoid lugging.

Mike

 

Nope.... You are simply keeping it in the power band. In fact, just keeping it from constantly changing gears, like in downshifting for sudden bursts, is probably better for the trans. Less times changing gears, less wear. Funny thing is, I don't J-gate battling O-holes on Rt8 because I'm scared I'll hurt the motor verses the trans. I let the trans decide how to shift since I'm always punching it to get around yet another dip sh*t that doesn't know how to drive. Then again, it would probably shift a lot less if it had a V8. And, I feel ya about the Massholes, visited my sister when she still lived in Salem..Yikes! I haven't visited them in their new house in Boxford yet, but she says it's much better out there...

 

Bull27 - what MPG do you get?

If lower than it would be I suppose you're doing higher revs, using more gas, which generates more heat. Lots of things are working a bit harder but it's not exactly that which kills a car (short journeys, rust, non-use, etc are the devils). I'd be making sure to do regular oil changes, which I think you do. The tranny is my pet worry but I really do not know whether it will be running any hotter than it would (it has temp sensors but generic OBD can't read them). Fewer shifts actually sounds like it should be better.

Heck, I'd just do what you like. It's a tool and a joy so enjoy

 

I dont blast it from the line (for many reasons), my biggest joy is to launch in 2nd or 3rd from around 2500. Love it, and I also love the exhaust note when you are slowing down and the engine winds down from 3500-4000, amazing. I can honestly not see any car keeping up with the STR in such circumstances. From the line, obviously that is its weak point.

JOS: Salem is child's play compared to the greater Boston area, but still bad in pretty much any part of the state. It is a battle of wits, *****, out manuevering, and straight up being a d*ck. People are so impatient, if you delay for 1/2 second when the light turns green you are getting beeped, thrown the bird, yelled at or all of the above. I have never experienced so much RAGE during certain commutes with SO many jerks, A holes and people that legitimately should not be on the road.

Jag: To be honest I have NO idea what my gas MPG is. I only track it when going on long trips. I was just concerned about sticking in one gear for too long i.e. 3rd. I know in all my standard vehicles I would, but was skeptical seeing that this is truly an automatic with a little play tool (J-GATE)

 

I've asked the Jag techs here if frequent J-gating might be responsible for the two bolts that hold the transmission cable in place underneath the car to come loose and fall off, rendering the transmission unable to shift. Folks seem to report this problem every couple of months or so on this forum. Never got a response from the techs, so I suppose J-gating isn't an issue....

Not long after I purchased the car for my wife, she asked about the J-gate side of the shift lever. I just told her that Jaguar put it there to encourage owners to tear up their transmissions by trying to pretend they had a manual, thereby creating much more service revenue for Jaguar. End of story. I want the car making the decisions when to shift, not her. She hasn't driven a manual since the 1980s and I surely don't want her tearing up that ridiculously expensive ZF....

 

It does seem that it may have something to do with it, as putting a bolt into it from the one repair I read seems to render the J-gate side inoperable.

That's the BEST thing I have ever heard as far as what you told your wife... How absolute it the J-Gate. Will you bounce off the rev limiter? Or will it realize you're a moron and take matters into it's own hands to protect the trans?

George

 

Unless they got the software wrong it will rev limit. So, I don't think it has any more to do to protect the trans. If you're in 2nd at red-line for long enough I wonder if the engine overheats? It should still just go into RP, though.

 

.......i use the j gate frequently for said benefit. The bolts fall out cause theyre loose, not cause you use the j gate. And they fall out you dont get to move the trans with shifter use. The best thing to do is just ask to have the bolts snugged when you have an oil change done its 2 sec...

 

Good to know, thanks Brutal, and to everyone else who responded. So the
consensus is that it is NOT harmful to your vehicle, whether it be tranny, engine overheating etc.

I wonder how much is enough though, cruising on the highway in 4th for long periods of time is great for pick up and performance, poor MPG, but it just SEEMS like its not right and should do some damage.

Also, is actually downshifting when slowing down an absolute no-no?

 

Im going to take a different tack. I think its acutally better for your transmission. If your going to accelerate your car at the same rate or maintain the same speed, the output power (RPM * torque) is the same on the output shaft of your transmission. On the input side, you still need to generate the same amount of power so with higher RPM in a lower gear, there is less torque stress on the transmission. This also applies to the engine, higher RPM and lower torque for the same given output power. I think the MPG is a stronger function of the engines load. For the same load, I think the hit in MPG due to less efficency at non-optimal higher RPM is small. I also willing to bet that people who selected the STR over the other offerings didn't rank MPG very high as an important feature


IMO, the old 3 and 4 speed auto transmssion were great and had predictable shift points so you could adjust your driving style to fit your mood unlike the 6 speed random (read adaptive) ZF. I think the only reason the industry moved to 6 or more speeds is to keep the engine in a more efficient zone to minimize the CAFE fleet average fine and to avoid charging a gas guzzler tax.

 

I use mine to downshift too, and in my nissan, and my suburban....

 

Ive found that the J-Gate is easier to use than most other comparable shifting mechanisms. The pattern is more intuitive as well as the shifts themselves are more positive. Most other patterns have you push for upshifts and pull for downshifts and then you wait for the transmission to react. The knob is also nicer than the usual t-handle. What would make the J-Gate mechanism perfect in my opinion would be if you could pull back for upshifts and push forward for downshifts like Indycars did in years past.

Mike

 

Damn I didn't know Nissan and Chevy had J-Gate's

 

Nissan has "L" gate
ill post a pic of the shifter in the sub some time

shifter in the Sub

a "work in progress"