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captincl

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Discussion starter · #1 ·
Hey fellow Patriot Drivers!

So wanted to get some thoughts from the community here. I've got a 2011 Jeep Patriot with CVT at 120k miles. Over the past year I've been experiencing jumpy accelerations and even decelerations (i.e. just touching the gas pedal from a stop the vehicle jumps forward very easily/uncomfortably, while accelerating (between 25-60 mph) each 'shift' of the transmission seems unevenly spaced/poorly timed with revs climbing into the 3.5k range before the bumping back down into the next 'gear', climbing hills the revs increase aggressively, and even while decelerating from cursing speed 60 or 75 mph, sometimes the vehicle will kind of 'hiccup' during decelerating. Full dealer tune up was performed last year at 100k miles (CVT oil flush, new spark plugs, Transmission control unit software update) A failed speed sensor was also replaced around this time.

Today I had my jeep in for routine service and was given a 2015 loaner Patriot with CVT at 45k miles. This vehicle was significantly smoother at all points of acceleration or deceleration. Revs while accelerating were at a much more evenly spaced ratio, and while hill climbing at cruising speeds, revs stayed consistent with engine digging in rather than tack jumping up to a ridiculous level.

Any thoughts - am I just driving an older worn out CVT? Did something go haywire with the Transmission control unit software update? should I be considering new spark plugs, etc? Thanks!
 
#2 ·
It doesn't sound like plugs to me. The tranny would be expensive so I'd try almost anything else first.

Elsewhere on this site I mentioned a different problem (stuttering on acceleration) and I think it was related to uneven tire wear, i.e., I had good rubber on one axle and worn rubber on the other. I think the mixed tire speeds were confusing the ECM. If your tires are inconsistent in size or wear, try that.
 
Discussion starter · #3 ·
Ignatz -

Interesting, how did you know I need new tires! This is exactly the case. In fact I've been unable to rotate the current tires for much of their lives due to a significant balance issue found 1 yr after their install, so front tires wore much more significantly than the rear. I plan to replace in the next month or so. I will report back if issue continues after the new tires. Thank you for the promising insight!
 
#4 ·
captincl, if it helps, in my case the good rubber was up front and the junks were on the rear. All the tires were 215/65-16s so slightly undersized. In my case I'd just had the transmission replaced under warranty so I couldn't imagine that was the problem, but it felt like the tranny was slipping, The problem was most pronounced when I was already moving and then accelerating to a higher speed, e.g. leaving a town, on an entrance ramp, or accelerating up a hill. It was happening in the spring and the problem went away when I put on a new set of summer tires.
 
#5 ·
CVT doesn't have gears, so it shouldn't be jumpy at all on acceleration, though a slipping feeling could mean it's on its way out. Fluid and filters should really be changed every 60k or less no matter what, but especially so if you're rough on it at all. Computer could also go haywire if you have different size tires like Ignatz mentioned, especially on an AWD/4x4. Different tire wear to the extremes mentioned in the last couple posts here might just be it. Always worth it to check the CVT though, just in case. Maybe add a Hayden 678 aux cooler while you're at it, maybe even switching to AMSoil or Valvoline fluid?
 
#7 ·
eddy4753 said:
Not trying to hijack thread but, Have similar problem. Have new rubber with about 4,000 on them with 53,600 original miles on jeep. I might change plugs tomorrow and see if that's it, otherwise, ?????????

Thanks
eddy
Click to expand...
If it's not the plugs, get the CVT fluid flushed/refilled(AMSoil or Valvoline), both CVT filters changed out, cross your fingers and pray. If it's still slipping, then there's two possibilities.

1. it's not the CVT(maybe because you don't have one, maybe not). In this case, look for other possibilities. Bad boots on the spark plugs, something in the timing, I don't know. Grasping as straws here for more possibilities.

2. Worst case scenario, but you'll need to start shopping for another CVT. They run $5,000 for a brand new replacement, an independent shop can get you a rebuilt model for $2,000-$3,000 not counting labor, or if you know where to look you can get a low mileage JATCO JF110E from a junkyard or other used parts dealer for a good price. Make sure year matches 2007, 2008-2009, 2010-2017. Also will need to match low range or not, 4x4 or not, and which engine.
 
#8 ·
eddy4753 said:
Not trying to hijack thread but, Have similar problem. Have new rubber with about 4,000 on them with 53,600 original miles on jeep. I might change plugs tomorrow and see if that's it, otherwise, ?????????

Thanks
eddy
Click to expand...
Eddy, don't worry about your CVT failing or an alien invasion -- neither is likely. Since you've got new tires and only 50,000 miles on your transmission, your problem is most likely the plugs. I presume you haven't changed them? If not, its seriously overdue. Patriot plugs are only good for 30,000. I stretch mine a bit past that but never go to 40,000. Some folks on here have gone longer, but then we get threads like these. Changing plugs is an easy task and shouldn't run much over $20. Several threads on here about changing plugs, and some include some helpful hints. (I like the hint about using the coil-pack to start the new plugs).

However, Rosso is right about changing the tranny fluid in the 50-60,000 mile range. The Owners Manual recommends double that
but IMHO its worth the money to get it changed far earlier. Its fairly expensive on a CVT compared to a conventional automatic, but its still a lot cheaper than a new tranny down the road.

Putting these thoughts together, I've noticed that even with old plugs, the engines in my Patriots idle smoothly, but will hesitate under stress. I wonder how many transmissions have been replaced because someone thought their CVT was failing when in fact it was tired spark plugs?

"Good Morning Mr. Service Manager, my Jeep is a piece of junk. The transmission is slipping."
"Yep, Sonny Boy, that's a big problem with these. The good news is that we can pop a new one in there for only about four grand."
"Yipes! $4,000? I can't afford that."
So he goes off to the junkyard, gets a used tranny out of a wreck and his brother-in-law helps him install it. He's out of it for $2000. :)
:( Oh no! The replacement tranny is also 'slipping' (or so he thinks). Try returning a bad transmission to a junkyard -- there is no joy in Mudville.
Now he's convinced that CVTs are trash and comes on this forum ranting about how bad CVTs are.
All for want of a set of spark plugs.

Eddy, replace those plugs and think of what you else you can spend $4000 on.
 
Discussion starter · #9 ·
Ignaz, same deal with you on the tires. Was finally able to rotate them this past spring, so good rubber is now in front. Noticed the problem began around that time, and especially prevalent when already moving, up on ramps, etc. Expecting new rubber will do the trick.
 
#11 ·
captincl said:
New tires this past fall and the jumpy accelerations have gone completely away. Confirmed uneven tire wear causing the issue. Thanks everyone!
Click to expand...
This is at least the second time someone has verified this as a cause for stuttering acceleration, and that is exactly what this forum is for! :) What might have been a monumental expense (or the final trip to a junkyard) was saved by another owner's unlikely theory that was shared, tried, and proven.

Thanks for the confirmation, captincl! Hopefully others will see this and not blame their transmissions.

Now I'm curious to know if this happens with conventional automatics, too.
 
#12 ·
captincl said:
New tires this past fall and the jumpy accelerations have gone completely away. Confirmed uneven tire wear causing the issue. Thanks everyone!
Click to expand...
We just bought a 2009 Patriot Sport (dumb 2WD one) with about 121K, and just noticed this issue. We've been pretty worried now, cause I haven't heard a ton of good things about these CVT transmissions, and was scared it's going out..

We've had it for just under 2 weeks, and didn't notice the issue at first. We just got 4 new snow tires put on, but it's also been between -20 and -5 where we live, so maybe it could be sorta same issue? Cold hard rubber with deep treads, on cold ground.. does that maybe make sense?

I plan to disable the esc or whatever it is and see if that changes anything..
 
#13 ·
shaunspelledright said:
We just bought a 2009 Patriot Sport (dumb 2WD one) with about 121K, and just noticed this issue. We've been pretty worried now, cause I haven't heard a ton of good things about these CVT transmissions, and was scared it's going out.
Click to expand...
Nothing dumb about a FWD Patriot. We liked our first (2.4 CVT) so much we got another (2.0 5-spd).

CVTs actually have a better repair record than conventional automatics. Problem is that while there is little to go wrong with a CVT when it does have problems, there is little to fix either, so it must be rebuilt or replaced.

I much prefer the CVT in snow -- the shifting is literally seamless which is great for hill-climbing. The power surge from a manual or conventional automatic can break the tires loose and with FWD that's not a good thing. Just last week I conducted my own test and discovered (to my surprise) that my FWD CVT could start on a hill when my FWD manual could not. No matter how I tried to ease the power, the manual broke loose and I began sliding back down the hill. In the same place my CVT did fine and I tried again on a steeper part of the hill and it got me going even there. The overall grade was about 15% but that part was steeper, and I was on new snow over packed snow.
shaunspelledright said:
We've had it for just under 2 weeks, and didn't notice the issue at first. We just got 4 new snow tires put on, but it's also been between -20 and -5 where we live, so maybe it could be sorta same issue? Cold hard rubber with deep treads, on cold ground.. does that maybe make sense?

I plan to disable the esc or whatever it is and see if that changes anything..
Click to expand...
The issue? Misfire under stress? Probably spark plugs.

ESC is a button to play with. You can purchase buttons at the dollar store for front and rear machine guns. They're buttons; guns & bullets not included.

You've probably got a spark plug problem = cheap easy project -- this time of year its best done in the garage; if not, I'd wait till spring. BTW, if your tranny is still slipping in the spring, then it wasn't the tranny. :D
 
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shaunspelledright
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