19' Intermittent Rough Ride (Rear Axle)

[ORTrux]

Managed to make some improvement to the ride:

• Did a ride height recalibration via Forscan. Truck was reading ~ -10/-5 sitting on level ground (measured actual ride height and it was even.) That seemed to help some with initial hits over bumps etc.
• Aired down a little more, but I'd been focusing on the rear end pressure since that was the harshest. I aired down the fronts some more because they were still getting up higher than I'd like when warm. Shot for ~37 hot up front and the ride seems a lot more consistent on the back axle as well. Take this with a grain of salt but I think maybe the fronts pumping up was resulting in the VDM seeing exaggerated movement over small bumps and stiffening the rears more than it needed too. There's a big emphasis on the rear tire pressure on here but the ride sensors are up front and if the sensors are seeing a lot of movement a more compliant tire might otherwise smooth out, might well be causing the rear axle to firm up.

Need to kick around some more and see if it holds up but for now it seems like it's gone from occasionally rattling my teeth to more what I'd expect from driving others.

 

[Wilbur]

At any rate, love the truck, however I've been trying to track down an issue where about 1/2 of the time the ride seems to go to shit. When when it's cold/been sitting, the ride is what I'd call smooth but firm - about what I'd expect from a Raptor. I test drove a couple and it feels right compared to those (and it's how it rode when I did the initial test drive.)

However, randomly after some period of driving it really seems as if the ride in the rear firms up dramatically and the truck will start getting unsettled going over rough pavement. IE, go over a pothole and you'll feel it in the front end a bit, but when the rear axle goes over it's harsher and there will be a second or two of vibration/shimmy from the rear - every now and then it'll rattle your teeth. Granted it's a live axle and this is a pickup, but it really feels like this effect comes and goes and the ride really takes a nose dive.

I want to bring this thread back to life because I'm experiencing the exact same scenario. - Just bought it end of December and I've put 1600 miles on it so far. 21k miles total. It's happened every now and then where the first 15 minutes of a drive it feels super smooth then just seems to ride a lot rougher out of no where. Up until now I passed it off as just the road surface. Now it is a constant rough ride coming from the rear... So bad that I was going around a curve today at 50mph and it feel like it started hopping and shaking the rear end. I immediately slowed down and pulled over to check everything over. I drive this road almost every week and it has never done this before. In fact I usually go 55-60 around it and it feels very planted. (Speed limit is 55 on this section).

Only thing I can think of is about two days ago I was 30 minutes into my drive home from work and experienced really bad wheel hop from a stop. I let off but I'm wondering if it still did some damage. Just seems that ever since then its now a rough ride. I was trying to shrug it off until that incident today with the curve.

For reference my current tire pressure is 36f, 33r (cold).

Any ideas?

 

[LeadFootLarry]

I just checked my LR & RR sensor Voltages and they were both at 0.00 while the LF & RF both had positive voltage values. Is this normal?

 

[ORTrux]

I want to bring this thread back to life because I'm experiencing the exact same scenario. - Just bought it end of December and I've put 1600 miles on it so far. 21k miles total. It's happened every now and then where the first 15 minutes of a drive it feels super smooth then just seems to ride a lot rougher out of no where. Up until now I passed it off as just the road surface. Now it is a constant rough ride coming from the rear... So bad that I was going around a curve today at 50mph and it feel like it started hopping and shaking the rear end. I immediately slowed down and pulled over to check everything over. I drive this road almost every week and it has never done this before. In fact I usually go 55-60 around it and it feels very planted. (Speed limit is 55 on this section).

Only thing I can think of is about two days ago I was 30 minutes into my drive home from work and experienced really bad wheel hop from a stop. I let off but I'm wondering if it still did some damage. Just seems that ever since then its now a rough ride. I was trying to shrug it off until that incident today with the curve.

For reference my current tire pressure is 36f, 33r (cold).

Any ideas?

It was somewhat better after doing the stuff I mentioned but I ended up breaking down and swapping the shocks with a full set of ~50mi take offs I picked up from a SoCal truck builder. I think it is related to heat in the shocks and it's either the fluid or seals/bushings going wonky idk. I had 10k miles on you though so I'd be surprised if yours are worn yet, unless the previous owner really drove the truck hard. FWIW I paid around ~$1100 for the shocks delivered but I think they're a little harder to come by now. I had Ford swap then on for me while they were replacing my transmission that detonated and they were actually pretty fair/good about the labor and I wanted to make sure it was on the record with them since I was about to purchase an ESP thru Flood. Worked out well in the end.

 

[ORTrux]

I just checked my LR & RR sensor Voltages and they were both at 0.00 while the LF & RF both had positive voltage values. Is this normal?

The sensors ideally will read ~0.00 at rest but uneven ground or any load on the transmission will result in a slight change. If the voltage is markedly higher you might want to do a recalibration, but drive around a bit first and then park on the flattest slab you can and check the values then so things are settled.

 

[Raptor Tony]

did you try a live valve reset?

how does one do this?

 

[ORTrux]

how does one do this?

w/ Forscan. It's a procedure you can run, takes 5 minutes. Just need to park the truck on level ground, get out of it, and tell it how much fuel is in the tank - will reset the sensors back to 0. Accounts for the springs settling and is definitely required if any mods are done like a leveling kit.

 

[Wilbur]

w/ Forscan. It's a procedure you can run, takes 5 minutes. Just need to park the truck on level ground, get out of it, and tell it how much fuel is in the tank - will reset the sensors back to 0. Accounts for the springs settling and is definitely required if any mods are done like a leveling kit.

Should you do this when you get Deavers?

 

[ORTrux]

Should you do this when you get Deavers?

I believe yes. Ford should be doing it basically any time they futz with the suspension meaningfully and most truck shops that know something about Live Valve know to do it as well, but YMMV, and if they didn't tell you they did it I wouldn't assume it. Whether or not it makes a huge difference for rear springs idk, but people that level their trucks say it does for sure - since the front sensors are going to think the suspension is slightly extended at all times.

 

[FordTechOne]

FYI, there was a software calibration update released for 2019 models built on or before 15-Nov-2018 to correct a harsh/bumpy ride concern. So if your truck falls within that build date range you’ll want to have the VDM updated.