F150 Rear Sway Bar for head bobble?

[TacoFergie]

Does adding a rear sway bar help with how the truck rocks and causes the driver and passenger to head bobble/sway side to side when entering or exiting parking lots? I know they help with handling, but I wonder if it helps with the lower speed?

It's for my 23 F150, I've considered trying a rear sway to improve that. But I haven't seen much reference to what I'm asking.

 

[Cujet]

Head toss is made worse by anti sway bars. The more compliant the suspension, the less the head toss.

However quite often people prefer a taught suspension with excellent damping as the overall ride is more pleasing. And they put up with excessive head toss to enjoy better road manners.

The F150 lighting EV with its IRS rear suspension and low CG is a better riding F150. Try one (if you have not done so already) and see if that configuration is better.

 

[AZjeff]

You're talking about how the truck rocks side to side when going over a transition like a curb or drainage channel diagonally? Highly doubt it would have any affect on that. Adding an anti-sway bar in the rear when there isn't one will make the truck want to oversteer at some point in higher G turning.

What ^ he said.

Slow down.

 

[TacoFergie]

Head toss is made worse by anti sway bars. The more compliant the suspension, the less the head toss.

However quite often people prefer a taught suspension with excellent damping as the overall ride is more pleasing. And they put up with excessive head toss to enjoy better road manners.

The F150 lighting EV with its IRS rear suspension and low CG is a better riding F150. Try one (if you have not done so already) and see if that configuration is better.

Well then, I guess a sway bar is out of consideration then. It's quite comfortable ride and I don't mind the handling. It's much improved over my previous Tacoma, but if I could make it better for a reasonable investment, I would.

You're talking about how the truck rocks side to side when going over a transition like a curb or drainage channel diagonally? Highly doubt it would have any affect on that. Adding an anti-sway bar in the rear when there isn't one will make the truck want to oversteer at some point in higher G turning.

What ^ he said.

Slow down.

I don't go fast when leaving or entering parking lots. Heck, I don't really drive quick much anyhow except the highway on longer trips. But some with the curb transition built into them are nearly impossible to avoid the side to side movement unless I go about 2-3 mph or purposely turn sharper to hit it straight on.

I'm really just nitpicking, it's still a far better ride than my previous 15 Tacoma. The only truck I can recall driving with leaf springs and a rear sway bar was a few 2nd gen Tundras when I installed the TRD lowering springs and sway bars on them, but thats been over 15 years ago...so I don't recall the ride or handling differences anymore.

 

[bimiko939]

Yeah, a sway bar would definitely make that diagonal curb wobble worse, it just ties the two rear wheels together more rigidly. Honestly, if you want to tame that side-to-side rocking without ruining the ride, a good set of rear shocks (like Bilstein 5100s) makes a night and day difference on these F150s

 

[TacoFergie]

Yeah, a sway bar would definitely make that diagonal curb wobble worse, it just ties the two rear wheels together more rigidly. Honestly, if you want to tame that side-to-side rocking without ruining the ride, a good set of rear shocks (like Bilstein 5100s) makes a night and day difference on these F150s

Are the 5100's an improvement on the F150? I really haven't looked into shocks since I'm not looking to lift it at all. On my Tacoma the 5100's were more harsh than the OE TRD Off Road Shocks, especially on sharp bumps like slight road heaves. Heck, sometimes the rear felt jittery or unplanted on certain road conditions. I want to avoid that for sure on the F150.

 

[IndyIan]

I think you are right, that adding a rear sway bar would reduce head bobble, as it would try to keep the chassis level as the inner front tire start climbing the grade before the outer one does. It would reduce the understeer tuned into the chassis though. I guess stiffer rear shocks would help a bit, and be the easiest to try.

Lowering the whole truck would help, or getting softer springs all round would allow you to run a softer front sway bar, while keeping the factory level of understeer in the suspension setup.
Disconnecting the front sway bar might be something to try, I think now the manufacturers dial in a ton of understeer, and running without the front swaybar is still reasonable to control, but probably not recommended if your frequently going over 60mph.

I was amazed this winter of the grip of my Impreza on slippery roads, but it kept bottoming out the outside front suspension on bumps I didn't recall it happening before, like briskly entering a steep parking lot... Then when I switched to summer tires, I realized I had been driving most of the winter with a broken front sway bar link... Supple suspension is good in low grip conditions. I fixed the link and now rarely bottoms out. I never felt it trying to bring the rear around even with no front sway bar, as the rear springs are quite soft on it.

 

[DCDG]

I custom installed a Bell tech rear sway bar on my 98 F-150 required drilling the ladder frame to locate the links. Can't tell you about head bobble but made the truck anchored down also swap out your front rubber sway bar bushings for urethane. Not my leak co-workers car was the leaker.

 

[TacoFergie]

I think you are right, that adding a rear sway bar would reduce head bobble, as it would try to keep the chassis level as the inner front tire start climbing the grade before the outer one does. It would reduce the understeer tuned into the chassis though. I guess stiffer rear shocks would help a bit, and be the easiest to try.

Lowering the whole truck would help, or getting softer springs all round would allow you to run a softer front sway bar, while keeping the factory level of understeer in the suspension setup.
Disconnecting the front sway bar might be something to try, I think now the manufacturers dial in a ton of understeer, and running without the front swaybar is still reasonable to control, but probably not recommended if your frequently going over 60mph.

I was amazed this winter of the grip of my Impreza on slippery roads, but it kept bottoming out the outside front suspension on bumps I didn't recall it happening before, like briskly entering a steep parking lot... Then when I switched to summer tires, I realized I had been driving most of the winter with a broken front sway bar link... Supple suspension is good in low grip conditions. I fixed the link and now rarely bottoms out. I never felt it trying to bring the rear around even with no front sway bar, as the rear springs are quite soft on it.

That was my thought process as well, stiffening it in a lateral direction to keep it from going back and forth.

Swapping springs is not something I'm interested in as I want to keep it stock height. Shocks, probably at some point. With my previous 2nd gen Tacoma I had a few suspension setups over the years. The one that rode the best that I wished I wouldn't have removed was 3rd gen TRD Off Road front shocks/springs and rear shocks (I did a giant write up on TacomaWorld). It felt more balanced front to rear and rode better than the stock suspension and even Bilstein 6112's. Oddly enough, the 3rd gen front spring rate is 700lbs compared to the stock 2nd gen being around 500lbs and Bilsteins 600lb. Either way, that setup was awesome and I learned a stiffer spring doesn't always mean a stiffer ride, its all in the shock/strut damping. Long story short, I think you may be onto something with your assesment as well.

Hmm, you've given me more to think about now.

 

[tcp71]

bilstein 4600s are the bilsteins you use if you run it at stock height. Have had them on the rear of my 2016 since new. Better controlled, but no idea if your head will bob less.

 

[DCDG]

That was my thought process as well, stiffening it in a lateral direction to keep it from going back and forth.

Swapping springs is not something I'm interested in as I want to keep it stock height. Shocks, probably at some point. With my previous 2nd gen Tacoma I had a few suspension setups over the years. The one that rode the best that I wished I wouldn't have removed was 3rd gen TRD Off Road front shocks/springs and rear shocks (I did a giant write up on TacomaWorld). It felt more balanced front to rear and rode better than the stock suspension and even Bilstein 6112's. Oddly enough, the 3rd gen front spring rate is 700lbs compared to the stock 2nd gen being around 500lbs and Bilsteins 600lb. Either way, that setup was awesome and I learned a stiffer spring doesn't always mean a stiffer ride, its all in the shock/strut damping. Long story short, I think you may be onto something with your assesment as well.

Hmm, you've given me more to think about now.

Do you have a tonneau cover? I noticed the truck being stiffer with the addition of a tonneau. I was always a car guy but wanted a pickup at the time for loading the bed with pavers mulch soil taking larger items to the landfill but also wanted something playful. I raised the front 1.5" using urethane spring spacers replaced front sway bar bushings with urethane all four shocks were replaced as per budget I installed SEN-SEN shocks a long with the bell tech rear sway bar. While I was at it I had the lower control arms replaced they were in rough shape had wide Kumho HT tires the truck was nailed down I thought the 1.5" lift would be detrimental but realized installing the spacers the springs are loaded point being the truck rode wonderful and smooth and stayed well mannered on twisty roads and off ramps. If you play your cards right you could achieve great handling without sacrificing ride and occupant comfort.

 

[meep]

I ran hellwig rear sway bar on my f150 and it was fantastic. It may be a little stronger than it needs to be, but the hellwig has 3 settings, and on the lowest it was quite nice. It also radically transformed on-center steering feel. With that, normal 18” oem wheels, and eventually a reasonable shock tuning in the back, it handled similarly to an accord, frankly. If I buy another f150, it would be one of the first things I’d do to it.

Put a trailer behind it or a load in the bed, and it’s even better.

@TacoFergie

 

[TacoFergie]

Do you have a tonneau cover? I noticed the truck being stiffer with the addition of a tonneau. I was always a car guy but wanted a pickup at the time for loading the bed with pavers mulch soil taking larger items to the landfill but also wanted something playful. I raised the front 1.5" using urethane spring spacers replaced front sway bar bushings with urethane all four shocks were replaced as per budget I installed SEN-SEN shocks a long with the bell tech rear sway bar. While I was at it I had the lower control arms replaced they were in rough shape had wide Kumho HT tires the truck was nailed down I thought the 1.5" lift would be detrimental but realized installing the spacers the springs are loaded point being the truck rode wonderful and smooth and stayed well mannered on twisty roads and off ramps. If you play your cards right you could achieve great handling without sacrificing ride and occupant comfort.

I do have a tonneau cover. It's the Ford accessories version (made by BAK) of the BAK X4S which is a hard roll-up cover with vinyl over top. I typically stay away from poly bushing just due to squeaking over time that I have experieenced in the past.

As for suspension, it's all stock except I did remove the rear lift blocks to lower the rear about 1.5-2" so it still has some rake, but not as ridiculous as it was stock. Often referred to as "Reverse Leveling" in the F150 groups. Removing the blocks improved the brake dive, handles a little better, helps a lot with bed access and doesn't affect the ride quality. Because the factory rake was pretty high, the tailgate when opened is around 4" lower.

Here's a little before and after reverse leveling.

 

[TacoFergie]

I ran hellwig rear sway bar on my f150 and it was fantastic. It may be a little stronger than it needs to be, but the hellwig has 3 settings, and on the lowest it was quite nice. It also radically transformed on-center steering feel. With that, normal 18” oem wheels, and eventually a reasonable shock tuning in the back, it handled similarly to an accord, frankly. If I buy another f150, it would be one of the first things I’d do to it.

Put a trailer behind it or a load in the bed, and it’s even better.

@TacoFergie

Did you notice or remember have less head wobble when entering parking lots with the small curbs?

I have no complaints really with how the truck handles or rides. But if I can improve it without breaking the bank, that'd be pretty awesome. I do tow sometimes locally, but not frequently and I don't have any plans to tow long distances in the foreseeable future, but who knows what life has to throw at me. I'll probably have this truck for another 8 years, maybe longer. So I look at modifications as more of an investment into my enjoyment of the vehicle long term. I know....vehicles like this aren't really an investment. haha

 

[DCDG]

I do have a tonneau cover. It's the Ford accessories version (made by BAK) of the BAK X4S which is a hard roll-up cover with vinyl over top. I typically stay away from poly bushing just due to squeaking over time that I have experieenced in the past.

As for suspension, it's all stock except I did remove the rear lift blocks to lower the rear about 1.5-2" so it still has some rake, but not as ridiculous as it was stock. Often referred to as "Reverse Leveling" in the F150 groups. Removing the blocks improved the brake dive, handles a little better, helps a lot with bed access and doesn't affect the ride quality. Because the factory rake was pretty high, the tailgate when opened is around 4" lower.

Here's a little before and after reverse leveling.

View attachment 350449

Good looking truck. Yes the poly bushings can squeak a good heavy silicone paste normally resolves that. I think the front bushings I had were from Delco.

 

[Dave9]

Stiffer shocks give you more driving control but also more initial head bobble when one of your rear wheels hits a bump/curb/etc at a different time than the other one, though they can reduce the duration of the head bobble.

 

[meep]

Did you notice or remember have less head wobble when entering parking lots with the small curbs?

I have no complaints really with how the truck handles or rides. But if I can improve it without breaking the bank, that'd be pretty awesome. I do tow sometimes locally, but not frequently and I don't have any plans to tow long distances in the foreseeable future, but who knows what life has to throw at me. I'll probably have this truck for another 8 years, maybe longer. So I look at modifications as more of an investment into my enjoyment of the vehicle long term. I know....vehicles like this aren't really an investment. haha

Head bobble seemed a trade off. Before the bar, the truck leaned more and you were tossed farther. After bar, it leaned less but the corrective lean was quicker to come. Frankly, between the two, because the amount of rocking was less, I guess my perception is that the event didnt last as long. I am pretty picky - head bobble is worse on a taller vehicle in general. This didn’t seem worse. If anything, it may have been better because vehicle roll became the average between the two sway bars instead of only the front driving roll.

 

[buck91]

Does adding a rear sway bar help with how the truck rocks and causes the driver and passenger to head bobble/sway side to side when entering or exiting parking lots? I know they help with handling, but I wonder if it helps with the lower speed?

It's for my 23 F150, I've considered trying a rear sway to improve that. But I haven't seen much reference to what I'm asking.

It seems like this is impacted heavily by rebound damping to me. When switching from softer OE dampers to the fairly firm Bilstein 5100' the right didnt get SMOOTHER but it did improve drastically especially in the way you describe.