TSB 20-2277 2019-2020 Ranger - Shudder/Vibration When Accelerating From A Stop

[quangdog]

I thought it was about shudder when taking off/accelerating from a stopped position, not starting up the vehicle. I didn't know there was shudder when people start their trucks.

When @P. A. Schilke says "start up shudder" - he means when accelerating from a stopped position, not when starting the engine of the truck.

My truck exhibits this start up shudder behavior... here is my best description of the sensation:

Let's say I'm driving normally down a road with a speed limit of 40 mph. Truck is smooth while cruising, only feeling typical road sensations. Drivetrain is fine. Approach a stop light, and slow to a stop. As soon as the truck stops completely, the engine shuts down with the auto-start-stop feature. So now I'm sitting at a stop light in stealth mode - engine not currently running, just waiting for the light to turn green. When the light turns green, I let my foot off the gas and the engine immediately starts again. This produces a VERY NORMAL shudder in the truck as the engine starts - no problem, completely expected. Then my foot gets over to the accelerator pedal, and I pull away from the light with easy to moderate throttle input. Up until the truck hits about 7 mph the drivetrain is perfectly smooth, but between 8ish to 15ish mph, I experience a "shudder" in the drive train that *feels* exactly like the way the truck shudders when the engine starts up as described above. As soon as I'm moving faster than 15 mph, the shudder disappears.

The stronger the throttle input, the stronger the shudder, but the shorter the duration (because I accelerate faster).

As Phil said, if you feel a vibration while cruising at any constant speed above about 15 mph, it is NOT due to this "start up" shudder. This shudder is specifically caused by driveline angles being slightly out of spec, and is very common with 2 piece drive shafts, and specifically happens when accelerating from a stop somewhere around 10-15 mph.

I tried to get my truck into a dealer, but had a terrible experience with the service advisor lying about loaner car availability and misunderstanding / incorrectly documenting the actual issue I wanted checked. Attempted to drop the truck off once, but wound up leaving the dealer astounded with how I'd been treated. Just living with the shudder... but it bothers me.

Currently planning to attempt shimming the center bearing myself, just as soon as I have a spare few minutes to do so.

Mine is a 2019 Lariat FX4, with about 13k miles on the clock now. The shudder has been there since day 1, and was not altered at all by installing a 2" front leveling kit (Eibach) and new rear shocks (also Eibach).

I'm 100% convinced the root cause is driveline angles. I'm also 100% convinced none of my 3 local(ish) Ford dealer service departments will apply the TSB correctly.

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[rdgallo]

When @P. A. Schilke says "start up shudder" - he means when accelerating from a stopped position, not when starting the engine of the truck.

My truck exhibits this start up shudder behavior... here is my best description of the sensation:

Let's say I'm driving normally down a road with a speed limit of 40 mph. Truck is smooth while cruising, only feeling typical road sensations. Drivetrain is fine. Approach a stop light, and slow to a stop. As soon as the truck stops completely, the engine shuts down with the auto-start-stop feature. So now I'm sitting at a stop light in stealth mode - engine not currently running, just waiting for the light to turn green. When the light turns green, I let my foot off the gas and the engine immediately starts again. This produces a VERY NORMAL shudder in the truck as the engine starts - no problem, completely expected. Then my foot gets over to the accelerator pedal, and I pull away from the light with easy to moderate throttle input. Up until the truck hits about 7 mph the drivetrain is perfectly smooth, but between 8ish to 15ish mph, I experience a "shudder" in the drive train that *feels* exactly like the way the truck shudders when the engine starts up as described above. As soon as I'm moving faster than 15 mph, the shudder disappears.

The stronger the throttle input, the stronger the shudder, but the shorter the duration (because I accelerate faster).

As Phil said, if you feel a vibration while cruising at any constant speed above about 15 mph, it is NOT due to this "start up" shudder. This shudder is specifically caused by driveline angles being slightly out of spec, and is very common with 2 piece drive shafts, and specifically happens when accelerating from a stop somewhere around 10-15 mph.

I tried to get my truck into a dealer, but had a terrible experience with the service advisor lying about loaner car availability and misunderstanding / incorrectly documenting the actual issue I wanted checked. Attempted to drop the truck off once, but wound up leaving the dealer astounded with how I'd been treated. Just living with the shudder... but it bothers me.

Currently planning to attempt shimming the center bearing myself, just as soon as I have a spare few minutes to do so.

Mine is a 2019 Lariat FX4, with about 13k miles on the clock now. The shudder has been there since day 1, and was not altered at all by installing a 2" front leveling kit (Eibach) and new rear shocks (also Eibach).

I'm 100% convinced the root cause is driveline angles. I'm also 100% convinced none of my 3 local(ish) Ford dealer service departments will apply the TSB correctly.

That is a very good explanation of what this start up shudder is. Thanks for posting it!

 

[Rp930]

I’ve been reluctant to admit I had a tiny bit of shudder. Today in an effort to improve the ride for my wife, I put two 70 lb bags of sand at the front of the bed. Shudder gone, ride improved. Win-win.

 

[jamo147]

Question for Phil Schilke…. I had the TSB done to adjust pinion angle. It made it better but not fully fixed. I noticed that shudder is nearly negligible when you don’t stomp on accelerator and it is worse when you are an incline. I also recall reading a comment where a user upgraded springs to help fix start up shudder in an F150. Got me thinking, is it possible that the shudder comes back because the rear leaf is so flexible that you get torsional rotation of the axle upon acceleration, basically creating an excessive pinion angle? That may explain why so many rangers have it. I’m wondering if upgraded leaf springs would improve/fix it?

 

[Milkmaster]

Question for Phil Schilke…. I had the TSB done to adjust pinion angle. It made it better but not fully fixed. I noticed that shudder is nearly negligible when you don’t stomp on accelerator and it is worse when you are an incline. I also recall reading a comment where a user upgraded springs to help fix start up shudder in an F150. Got me thinking, is it possible that the shudder comes back because the rear leaf is so flexible that you get torsional rotation of the axle upon acceleration, basically creating an excessive pinion angle? That may explain why so many rangers have it. I’m wondering if upgraded leaf springs would improve/fix it?

I have had thoughts along these same lines. The rear end really flexes the leaf springs during acceleration more than I would have expected or have seen before on other vehicles.

 

[jamo147]

I have had thoughts along these same lines. The rear end really flexes the leaf springs during acceleration more than I would have expected or have seen before on other vehicles.

i have about 300 lbs in the bed right now lowering the bed. That improved but didn’t get rid of shudder initially. I did this because previously I observed that when the bed was loaded with 500 pounds, it fixed it. I initially attributed this to the lowered ride height/pinion angle. Recently after reading a reply to this thread that someone put 140 lbs at the front of the bed to fix shudder, I moved the weight more toward the center/front of the bed. The shudder is now almost gone so that is supporting that it’s a combo of excessive static pinion angle and axle torsion. Now the challenge will be replacing with springs that are stiffer but don’t raise the bed height since that may screw up the pinion angle again.

 

[quangdog]

I added spacers to the center carrier bearing for the driveshaft yesterday. This has greatly reduced the start-up shudder... it's not completely gone, but it's much, much, much better. Barely feel it at all any more.

I wound up using a stack of grade 8 washers and new, longer stainless steel bolts. Here are some pictures.

Before:

After:

 

[Willis]

My truck started shuddering at about 33k and it went to the shop today. They said it would take minimum two days to fix. Is this the normal time range?

 

[Willis]

My truck started shuddering at about 33k and it went to the shop today. They said it would take minimum two days to fix. Is this the normal time range?

Update it only took about an hour and didn’t help it at all. Not very happy.

 

[navsnipe]

Update it only took about an hour and didn’t help it at all. Not very happy.

It's odd that your shuddering didn't start until 33k miles. Did you recently do any suspension work to the truck? Most trucks that have the shudder come with it. Is the shudder only at take-off, around 10 to 15 mph?

 

[Willis]

It's odd that your shuddering didn't start until 33k miles. Did you recently do any suspension work to the truck? Most trucks that have the shudder come with it. Is the shudder only at take-off, around 10 to 15 mph?

Nope totally stock. It’s at about 30 to 45 mph is the worse. But highway driving is normal. If I am in town it is terrible. Been totally happy with my truck as I have had many Rangers in past and my dad has also. He still has his 97 splash in the garage lol. But to have the mechanic verify it is fixed when it isn’t really has made me down. I don’t want to keep running to the car lot as I like everybody else just doesn’t have the time.

 

[navsnipe]

Nope totally stock. It’s at about 30 to 45 mph is the worse. But highway driving is normal. If I am in town it is terrible. Been totally happy with my truck as I have had many Rangers in past and my dad has also. He still has his 97 splash in the garage lol. But to have the mechanic verify it is fixed when it isn’t really has made me down. I don’t want to keep running to the car lot as I like everybody else just doesn’t have the time.

I would suspect this isn't the same take-off shudder that TSB 20-2277 covers. As much as you don't want to have to go back to the dealership you will probably have to. Make sure a tech does a ride along with you so you can show when and where the problem happens. Do you have a description of the work they did recently?

 

[Willis]

I would suspect this isn't the same take-off shudder that TSB 20-2277 covers. As much as you don't want to have to go back to the dealership you will probably have to. Make sure a tech does a ride along with you so you can show when and where the problem happens. Do you have a description of the work they did recently?

Yea they drove the truck and I rode with them before they did the tsb.

 

[quangdog]

Nope totally stock. It’s at about 30 to 45 mph is the worse. But highway driving is normal. If I am in town it is terrible. Been totally happy with my truck as I have had many Rangers in past and my dad has also. He still has his 97 splash in the garage lol. But to have the mechanic verify it is fixed when it isn’t really has made me down. I don’t want to keep running to the car lot as I like everybody else just doesn’t have the time.

30-45mph? That's definitely not start up shudder. More likely you have an issue with a wheel that threw a weight and is no longer in balance correctly.

Yea they drove the truck and I rode with them before they did the tsb.

Super odd that they would have applied that tsb (which specifically addresses shudders when first starting from a stop, not when cruising) after riding with you and feeling the behavior.

It's incredibly frustrating to me that the people who are supposed to be qualified to address concerns with these trucks seem not to be at all. :-(

 

[ChiefQM]

Yea they drove the truck and I rode with them before they did the tsb.

I am a slow convert to the start up shudder not being my issue. I have had techs and shop foremen ride with me and tell me that even though what they feel in my truck is the worst they have ever experienced with the bucking and shaking while steady in a gear (not shifting), the truck was operating as designed and neither their shop nor Ford was going to pay them to work on it. I gave up on them even attempting to find the problem. As suggested elsewhere in this thread, when I start the engine, I put it in tow mode (and strangle the auto start feature), That holds the trans to shifting later, and the engine rpms are kept to about 2000 RPM, and the issue has virtually gone away. I am assuming you have a tow package, obviously. Hit the button on the side of your shifter and you can see that the trans is not shifting to 8th gear by the time you hit 30 mph. If I am going to drive over 40 mph and at highway speeds, I take the tow mode off. And they did the TSB (wrong, but they did it) to shut me up.

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