Lurching 40 to 50 mph slight hill

[Dave LV]

Recently my H3 AT with 7700 miles has started to lurch climbing slight hills at 40 to 50 mph. Dropping it into third gear does not make it go away nor changing to premium gas. I have also added three bottles of Techron from Chevron. Still no change.

Anyone else experiencing this?

[Steve - SanJose]

Never experienced this in 17K miles so far.

S.

[f5fstop]

How's the idle? Is the engine light on?
Does it only happen when going up a hill?
Sounds like the torque converter clutch to me, which is engaged in 4th and 3rd gear, is going between locked and unlocked.
Could be an engine miss, but three cans of Techron won't help if it is. Techron is good for keeping the engine and injector clean, as well as the fuel sending unit (if using the right Techron).
Can't help much with a long distance diagnosis, suggest a dealer visit.

[Dave LV]

Since it doesn't go away when I drop into 3rd gear, I figure it can't be the AT torque converter locking/unlocking.
No check engine light.
No idle problem.

How does the center dif work? Engine compression problem? But then why only uphill?

Yep, visit to dealer is called for, but I expect they will say "Problem not found".

Can leases be ended due to fundamental flaws such as this if it can't be repaired - i.e. GM says it is normal?

[f5fstop]

Your third gear theory is wrong, 4L transmissions will lock in manual 3rd gear, as well as in overdrive 4th gear.
Possibly an engine compression problem, but if it is the cylinder head issue, it would cause a rough idle, and the PCM would pick up a misfire after certain counts and turn on the idiot light.
As for buy backs, is this your first problem? Call your lease company. But if it natural, it is between your lease company and GM.

I really don't know of any heavy vehicle with an automatic and limited HP that will not do some shifting around on mountain roads. But then again, I don't know if it is a shifting problem or a TCC problem, or something entirely different. Good luck.

[Dave LV]

Interesting. I did not realize that the H3's AT would torque lock in 3rd gear. My other cars only did it in top gear.

But I now believe you are right about the torque converter lockup being the problem. Today I kept the speed going uphill below the 40 mph where it locks up and sure enough there was no lurching.

Lease is with GM and it is the first shop visit - but not where I bought it.

Shifting is no problem with the transmission. I expect it to with the H3's weight/power ratio. Seemed fine until lately.

Still surprised that putting on the brakes doesn't release the lockup. My '01 Camaro did and it made it much more drivable.

[Dave LV]

So the dealer said the lurching/lugging was present in their three loaner H3's also and therefore is considered normal. And since the COMPUTER could find nothing (even though the tech felt the shuddering), it was obviously OK per GM warranty process - what ever happened to good old fashioned seat of the pants repair?

So it is becoming more and more noticeable, and I now dread driving my H3 vs the joy I had for the first 5000 miles.

And unfortunately I still have 31 months to go on my lease.

I guess I will try the GM appeal process, but eventually will most likely have to look into buying my H3 out of the lease and selling it for a huge loss.

I knew I should have bought a GX470. Never have problems with Toyota/Lexus, but I wanted to be patriotic and buy American. Boy what a sucker I was.....

[NEOCON1]

So the dealer said the lurching/lugging was present in their three loaner H3's also and therefore is considered normal. And since the COMPUTER could find nothing, it was obviously OK - what ever happened to good old fashioned seat of the pants repair? since there is about a dozen computers monitoring everything now days seat of the pants is useless

So it is becoming more and more noticeable, and I now dread driving my H3 vs the joy I had for the first 5000 miles. drive it hard till it dies and push the blue button

And unfortunately I still have 31 months to go on my lease. there is a 48 month waranty so dont sweat it drive it hard till it breaks or you get a warning light they can trace to something

I guess I will try the GM appeal process, but eventually will most likely have to look into buying my H3 out of the lease and selling it for a huge loss. drive it till it dies and push the blue button

I knew I should have bought a GX470. Never have problems with Toyota/Lexus, but I wanted to be patriotic and buy American. Boy what a sucker I was..... now you sound like a hummer hatin tree licking troll and an anti-american one at that ;)

[Dave LV]

Warranty is useless when the local dealer says "it is normal".

[HummerNewbie]

Is there another dealer around you can go to? Just because they don't want to do anything doesn't mean it can't or won't be fixed by another dealer. As far as should have bought the Lexus, go for it. It doesn't matter what type of vehicle it is, there will be people that have problems. I have known people who have bought a Lexus and had more problems than I have had with all the GM vehicles I have owned combined.

[Dave LV]

Drivetrain shuddering problem has worsened in last 1000 miles. Now happens pretty much full time. Feels like miss in engine plus unbalanced tires. After two tries, determined to be "normal".

My present guess is that it is the transfer case since it happens even when the transmission is in neutral.

I am surprised no one else is noticing this since according to the dealership all three of their loaners have the same shuddering.

By the way, lemon laws appear to be somewhat useless in that if it can't be repaired in X times (usually 3 or 4 tries), then the car must be bought back...but what happens when manufacturer says defect is "normal" after 2 repair attempts? A loop hole that needs to be corrected.

[f5fstop]

Find another dealer, that is not normal. As for the dealer's statment, do you believe a dealer who won't repair your vehicle? If a dealers cannot find the problem, they love to say it happens on all H3s. Then you go to a forum and find out it is not normal. Odds are the dealer is full of s**t.
Personally, with your miles and my guess at when you purchased the vehicle, I would go after the rear diff.
If you had the cylinder head problem, you should set a code for misfire. However, if your rear axle is going, it will give the same symptoms, especially the unbalanced tire feel. Early, prior to August of last year, some of the rear axles were produced with lapping compound left on the gears, and this destroyed the gear set.
If you have a legitimate problem, three trips to the dealer is as good as three attempts to repair the problem in most states.
I go back to my first statement...find another dealer.

[Dave LV]

Actually, I have no complaints with the local dealer. They are trying to fix it and opened a case with GM corporate, but GM is the one that is saying it is normal after directing certain tests be run. The dealer must now wait for a GM representative to OK trying part replacements such as torque converter, transfer case, etc, or to request an engineer come observe the problem. Without GM's OK, nothing more will happen except arbitration.

[Steve - SanJose]

Did you drive any of the H3 loaners to see if they really felt the same?

S.

[usetosellhummer]

Your dealer is weak, a call from the woner or GM can get things moving. Call Hummer customer service direct. You are too nice or your dealer is jerkin you. They did not build this many trucks to have this kind of problem. Did you won a truck before? The H3 is a truck and will react alot diffrent then fu fu unibodys. Make some noise and calls. Call who your lease is with. GMAC ? get some people working for you.

[lance-n]

I agree. MAKE SOME NOISE!!!
Don't forget to be grateful that you aren't over 1,000 miles from the nearest dealer!!! :eek:

[Dave LV]

Now at 12000 miles and vehicle still jerks at slight throttle once the torque converter locks. It is in the shop now to be investigated. The loaner has the same problem, if not worse, with only 1200 miles on it.

I am surprised that no one else has this problem since it appears to be a generic design defect according to what I've been told and experienced.

Perhaps driving on flat or slightly inclined roads at 40-45 mph is not common?

Oh, and to those who doubt, even my wife who is not a car nut notices the problem now. Also, I have driven probably 100 rental cars and owned about 20, none of which have had this anomaly. My guess it is related to the full time 4wd and how the slip shafts are arranged with the transfer case which is free to rock back and forth. Does anyone know of a shock absorber for the transfer case?

[deserth3]

Recently my H3 AT with 7700 miles has started to lurch climbing slight hills at 40 to 50 mph. Dropping it into third gear does not make it go away nor changing to premium gas. I have also added three bottles of Techron from Chevron. Still no change.

Anyone else experiencing this?

I had something like this in a 95 Blazer I owned. Turned out to be the throttle postiion sensor.
I finally figure it out by downshifting od flat land so the throttle was in the same position as going up hill. At that throttle point it would stumble or lurch depending how you look at it.

[NEOCON1]

i have a noticable surge too , but only when going down hill with cruise-control . it feels like slack in the 40-60 split in high range unlocked . feels like theres a load then no load , back and forth till hill flattens out . then seems as smooth as ever .

[marin8703]

Hey Dave,

I would love to try this out on my truck to see if I got the problem too, but I need some pretty exact info.

Can you tell me what you mean by a slight hill, about how many degrees. And again tell me at what speed I should drive. Also if there is anything else special that i should do. I wana do everything exact, is AC on, is Traction Control on or off, when climbing the slight hill at around how many rps is your ingine.

I live in chicago, not many hills around here, but if you get me this info so that i can repeat it, i am willing to go out to hoffman estates, about 20-30 miles out, theres some pretty nice hills out there.

Im one of those people that like to know if and when their vehicle has a problem even if it really doesnt effect them, thats why i wana check this out. Thanks!

[Dave LV]

Just above 40 mph with the torque converter locked, flat or slight hill (2-7 degrees), slight throttle that keeps torque converter locked but puts some load on drivetrain. AC on, but I don't think it makes a difference.

Jerks longtitudinally, like poor gas with engine miss but no engine light comes on.

Local dealer has requested GM to send an engineer to look at it. They have seen it on on several H3's but none as worse as mine.

[f5fstop]

Just did some extreme ascents in CO, and had nothing like this happen. Didn't downshift as fast as I would have liked, but overall, it ran the mountains surprisingly good.

[Dave LV]

Running in the mountains is no problem. I too did a trip in the CO mountains over the fourth and didn't notice it until I can back to town. As noted, it is mainly on flat roads going around 40 to 50 mph with light throttle.

[HummBebe]

I don't remember which thread I said it in, but mine also does this. The shop manager took it for a drive, with me in the truck and duplicated it.

He said he didn't know what it could be, maybe the TC sticking? He said he would have to drive a few others to see if they did the same, then he would get back to me.

I haven't heard from him regarding this, he probably forgot.

[marin8703]

hey i tried to recreate this but i wasnt able to. I was cruising at around 40 on a flat road and then also tried on a slight hill.

I didnt feel any tipe of lurching or anything. The engine felt smooth and held the rpms constant. I had a passenger with me in case i couldnt feel it but they didnt feel anything at all either.

[Dave LV]

So at least it isn't a universal design fault, I hope, based on your experience. Negates GM's "it is normal".

Just wondering, what temperatures were you all driving in? Here in Las Vegas, I kinda wonder if it started in March when the temperature warmed up, and when I was in Colorado it was cooler and not so noticeable.

[marin8703]

when i checked if mine had the problem the temp was around 80 degrees, however here the temp goes from as low as -10 in some winters to high 90s and in some cases over a hundred.
never experienced anything like you are describing in any temp.

[Dave LV]

Well, that blows my idea of high temperature causing it because it definitely occurs on mine at 80F.
Just noticed that I can't turn off stability control with the dash push button.
I wonder if the problems are related...

[Dave LV]

Duh, it helps to read the manual. Have to push the button for 5 seconds, and then a light on the left side goes on, not the button itself. Definitely not related. Unfortunately.:(

[Dave LV]

So finally called Hummer Customer Assistance after local dealer, rep and GM engineering have found no solution to lurching with about 10 days total of trouble shooting. They will be talking to the local dealer and then get back to me.

Does anyone know what is the next step to try to either get it fixed or get a buyback under the lemon law?

[HummBebe]

I don't remember which thread I said it in, but mine also does this. The shop manager took it for a drive, with me in the truck and duplicated it.

He said he didn't know what it could be, maybe the TC sticking? He said he would have to drive a few others to see if they did the same, then he would get back to me.

I haven't heard from him regarding this, he probably forgot.

Mine is fixed, Front differential Carrier Bushings.

[ChevyHighPerformance]

So finally called Hummer Customer Assistance after local dealer, rep and GM engineering have found no solution to lurching with about 10 days total of trouble shooting. They will be talking to the local dealer and then get back to me.

Does anyone know what is the next step to try to either get it fixed or get a buyback under the lemon law?

Make sure that you have in writing that they recognized the problem and couldn't find a solution. If you want out of the vehicle, there are law practices setup up for lemon laws.

[springer]

Mine has started doing something similar after I put oversized (35") tires on it. I have only had it do it twice but my fience who drives it daily says it does it pretty often. I just figured it was due to the oversized tires but like I say I have only felt it twice so I havent been able to really get a good idea of what it really is.

Keep us updated.

[Dave LV]

Mine is fixed, Front differential Carrier Bushings.

Can you provide the part numbers that were replaced?

And where/what are these bushings?

[Hmmm2]

I had a different issue going for 2.5 months. GM/Hummer Corp. strongly encouraged me to go to another dealership AFTER my service dept and Hummer tech (regional tech) checked mine out and said it was 'normal for H3's". I knew it wasn't normal. I also had to resort to GM Corporate Customer Service .. first, the cust. serv. person had to call the dealer to get their thoughts on the problem. When that person told me "it sounds like it's normal for H3's", I asked for the next person in line above her. It was the next customer service person above her who told me that another dealer might have a 'fresh pair of ears' and may have heard of my problem before. He was right. I finally bit the bullet and drove to another dealer who found and fixed the problem in ONE day. It has been 2 weeks and so far, so good. I drove up and down Mt. Charleston this past week in LV and didn't have any problems. I know you have one major Hummer dealer in LV .. are they the only ones available to you? Good luck! Keep us posted! (By the way .. my problem wasn't something normal).

[ChevyHighPerformance]

I had a different issue going for 2.5 months. GM/Hummer Corp. strongly encouraged me to go to another dealership AFTER my service dept and Hummer tech (regional tech) checked mine out and said it was 'normal for H3's". I knew it wasn't normal. I also had to resort to GM Corporate Customer Service .. first, the cust. serv. person had to call the dealer to get their thoughts on the problem. When that person told me "it sounds like it's normal for H3's", I asked for the next person in line above her. It was the next customer service person above her who told me that another dealer might have a 'fresh pair of ears' and may have heard of my problem before. He was right. I finally bit the bullet and drove to another dealer who found and fixed the problem in ONE day. It has been 2 weeks and so far, so good. I drove up and down Mt. Charleston this past week in LV and didn't have any problems. I know you have one major Hummer dealer in LV .. are they the only ones available to you? Good luck! Keep us posted! (By the way .. my problem wasn't something normal).

Could you please post what was replaced?

[Hmmm2]

Could you please post what was replaced? Sorry, I thought you were all probably sick of seeing my problem posted here for 2 and a half months. My H3 had that grind in the rear right wheel area when I'd come to a stop. We live on a hill, so going downhill, heating up the rotors .. the grind would get very noticeable as you'd get to a red light or stop sign. Two and a half months ... all I heard was that it was 'normal for H3's". Yet, no one else I knew with H3's had that problem. After encouragement from members here and the GM/Hummer customer service manager ... I went to another dealer who was at a considerable distance from where we live. The second dealer turned the rotors, replaced front and rear brakes .. put new pads. The service manager told me I had a warped rotor. He found the problem in ONE day and took care of it. Soooo, it wasn't normal for H3's!!!!!!!!! :twak:

[Wisha Haddan H3]

The 1st dealership couldn't find a simple warped rotor? :twak:

Glad it's fixed now

[Hmmm2]

The 1st dealership couldn't find a simple warped rotor? :twak:

Glad it's fixed nowGo figure. Very discouraging.

[Boar-Ral]

I have a similar problem with my 2005 H2.* Around 40 mph, if I am trying to maintain my speed or very gradually accelerate, the engine surges, you can feel it, and you can see the RPM rise and fall slightly.* If I try accelerating a bit harder, the RPMs increase and the surging disappears.* I went to the dealership and they recommended fuel conditioner, a new air filter, and throttle body service, because it appeared dirty.* They threw fuel conditioner in, I put in a new air filter, but didn't have time to get the throttle body serviced, though I did buy cleaner so I will be trying that soon.* The problem still exists, so I hope that it is the throttle body.* If not, I'm out a couple hundred for their "diagnostic."* I just thought I'd mention it, since those are relatively easy fixes.* Not the same vehicle, of course, but the limited similarities might be enough that the same solution might work for both.

[Dave LV]

Unfortunately, not the same problem. Mine bucks like poor gas or cylinder misfire, but neither are occurring, and the engine rpm is rock solid. Got a call yesterday that an engineer thinks it is caused by the exhaust system... but I think the front differential carrier bushings sounds more like what is happening. Time will tell as the dealer will look at it more next week.

And again to all, the local Hummer dealer is trying everything and is being responsive - it is a GM design problem that appears endemic to all H3s, more in some than others.

[Hmmm2]

And again to all, the local Hummer dealer is trying everything and is being responsive - it is a GM design problem that appears endemic to all H3s, more in some than others.
I'm sure your dealer's service dept. is doing all that they can. After all, it's in their best interest to keep you as a returning, satisfied customer. The guys (and gals) at my dealer's service dept. are also good people. The service mgrs appeared almost as frustrated as I was over my H3 issues. But what the GM/Hummer Corp Customer Service person had told me was true ... another dealer's service dept MAY have come across a similar problem to mine and know what to do. I think that my H3 may have been the first one in with the problem and they (first dealer) didn't know what to think of it after trying different fixes. The 2nd dealer obviously had another H3 with a similar problem like mine, so it was a quick fix for them. If your dealer can't locate your problem, then going to another for THIS concern may be your answer. Good luck and keep us posted. :)

[Dave LV]

Dealer has put on Toyo AT Load D tires and I would say about 70% of the shuddering is gone. Can someone explain why new tires would do this?

Kinda ties in with the problem first being noticeable at around 7000 miles, and getting worse with more miles.

[wpage]

Sounds like a good question for Goodyear tire!!

[Wisha Haddan H3]

Maybe the wheels weren't balanced right.

[Dave LV]

Goodyears were balanced twice by Discount Tire and three times by Hummer dealer. Made no difference.

Perhaps the thicker tread allowed the tire to absorb more the rotational jerkiness?

Or perhaps the tire is much heavier and the rotational inertia damps out the drivetrain? Hmmm. How to ADD weight to a wheel is something I have never seen written up before.

[wpage]

So Dave The Tires. That was it?:confused:

[Dave LV]

Unfortunately, the new tires after a few hours of driving really only reduced shuddering maybe 40%. Helped to have heavier ones, but not the cure. Still has the driveline shuddering enough to be annoying, particularly once you are tuned into it. Plus, LT tires ride harsher than P tires due to the higher air pressure.

[Hmmm2]

Dave, did you ever get your shuddering/lurching problems completely resolved, or, are you just going to live with it?

[Dave LV]

Buy back in progress....

[Hmmm2]

Buy back in progress....
Ohhhhh mannnnn! Ok .. this could be good. Are you going to go for an H2 this time??? :beerchug: