The 2.7L Single Cab Thread

Wish I could help ya. I have vibes at stock height lmao

 

I've delt with the vibrations for a while. Get the grinding noise coasting from 70 down to about 50 and once I hit 60 while accelerating there is a slight vib that starts to come up. Researching it there can be a wide range of what it is. I've been meaning to try 2 degree shims but just haven't gotten around to it. There is a vibration thread but lots of ones deal with the 2 piece shaft, not much on the regular cab single piece shafts.

 

Mine almost pulses. I think it’s partially tires but it also gets worse with engine braking or low rpm throttle. Thinking may be driveshaft angle. Is this bad?

 

Pulsing is another thing mine does at high speeds. Supposedly it isn't bad. Just annoying. There is a certain range of angle the shaft is suppose to be and when the rear is lifted it goes beyond that threshold.

 

Yeah the thing is tho mine hasn’t always pulsed, it’s like a very very slight rumble strip feeling in the pedals and steering wheel and sounds like coming from the rear, but the pulse meaning it seems like it’s a series of rumble strips spaced apart if that makes sense. Rumble, smooth, rumble, smooth, about one bout of rumble per second. Feels almost like somethings binding

 

First time driving the 4.0 in my dad’s 2006. Balls it has. The AT sure sucks though. This engine with the 5 speed MT in a RC would rip.

 

I went back through some of my posts and I had forgotten that I did have a slight vibration in a specific mph range (I forget the exact spot, but I think it was around 68-70 mph). So I would either keep it around 65-66 (which is the best mpg range with the auto) or slightly above 70.

The 5 speed issue was that the lift would pull the slip yoke out from the trans resulting in vibration or grinding. One solution was to put a spacer between the driveshaft and diff which would push the slip yoke back in. Try a search on that regarding regular cabs and see what pops up. 4Crawler used to sell custom spacers which helped quite a few people. Here's a link to his page with info on measuring what thickness you would need but I'm not sure if he is still selling/making them.

4Crawler Offroad Products - Driveshaft Spacers for Toyota, Ford, Dodge & Chevy Vehicles

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I installed a 3/4 spacer on my rc it’s a 5speed and really couldn’t tell much of a difference, still get grinding and vibes at 70ish. One thing to note is that either the indent on the nut that holds the flange to the tcase was either never staked or someone had replaced a seal but mine was very loose torqued it to speck and restaked it may want to check that.

 

When I drive my dads f150 it feels like a rocket ship lol. 2.7 ecoboost. 10 speed, 325 Hp, 400lb-ft. Not gonna lie I’m jealous of the power

 

I’m pretty stumped on mine tbh. Auto trans and get vibes at stock height. Only change is a 3+overload leaf pack, but it was a used pack and doesn’t sit really any higher than oem. Half inch maybe. Not enough that it should vibe. I wonder if it’s my torque converter but I really hope not. Or drive shaft out of balance

 

I never had vibes but did get the driveshaft rattle after lift. Was pretty bad decelerating from hwy speeds down to about 35. This would make it vibrate, but wouldn't classify this with vibe issues other lifted trucks have (specifically ex/dbl cab tacos without a solid shaft). I put a 1" spacer in and it mostly solved the issue. Can't feel it anymore but you can still barely hear it when the back window is open.

Edit- any truck I've driven has vibrated to some degree, and lifting it just exacerbates the problem. It's a truck not a sedan.

 

Honestly thinking I need new rear wheel bearings or pinion. Like I said, it hasn’t always vibed. Only in the last 15k miles or so. And I did recently install new front wheel bearings and rotate the tires but the vibes still there. It seems more noticeable when the driveline is loaded either by engine braking or throttle. So maybe there’s slack in the pinion bearing that gets taken up and connects the vibes to the pedal more noticeably when the driveshaft is loaded? (I know the pedal isn’t directly connected but I mean to say that perhaps as the driveshaft free spins with no load, the slack lets it sort of float and then when it’s loaded it transfers vibes to more places??) either way, I think I’m hearing a whir on decel from my passenger side like a wheel bearing. Given that the fronts are new, wondering if replacing the rears would have any effect on the vibes. I mean it def couldn’t hurt lol.

 

also getting slight vibes with mine. 5100s with 3rd gen coils and leaf packs plus a 1 inch spacer in the rear. Im guessing its about 2 inches of lift. Initially after lifting I was getting the 35-45mph "grinding/vibration" from the needle bearing. Installed the ECGS bushing and the 35-45mph vibration is gone but now I have a slight droning/rumbling right at 55mph.

 

Yup mines most noticeable at 55 as well. Highway speeds barely noticeable. Under 40, almost nonexistent

 

Does it sort of pulse once per second or so?

 

I wouldn’t describe it as pulsing it’s pretty consistent. Almost sounds like I have super swampers. I think it’s coming from the front left and I can very slightly feel it trough the pedal and steering wheel. It’s weird because before the ecgs bushing I only had a vibration/growling at 35-45 and it was quiet at 55. Before bushing the noise would go away in 4wheel drive. Now It is only between 55-60 and I don’t notice anything else at different speeds. I also have a very slight shudder when accelerating right at like 5mph but I’ve had that since I bought the truck with 30k miles (now at 150k).

 

Yeah ik my tires make some noise as they’re all terrains, worn a bit unevenly, and have over 25-30k on em now. But I’m not convinced that they’re the problem as I rotated em and still have the vibe. Replaced my sticking brake calipers and front wheel bearings so I’m really leaning towards something from the output shaft back: output shaft, driveshaft, pinion, rear wheel bearings

 

You're stock height? I don't remember what my pinion angle looked like when my truck was stock but yours points straight at the driveshaft, it looks like in the picture. I think with a short wheel bas 4x4 truck, it should be pointed down a little bit more, maybe your suspension is worn. When under load, your pinion will point up even more and that may be causing your vibes.

 

That’s kind of my train of thought as well, though i just climbed underneath and noticed I could get a little play in the slip joint. Tiny amount but enough to hear it. Could that be the issue or is a tiny bit of slip joint play normal? I’m not a trained mechanic, just basic stuff like power steering lines and springs and motorcycles and shit

 

Yeah I’m stock height but with a leaf pack from an access cab to get the extra leafs. I installed myself. Don’t think there’s any way I could’ve changed the pinion angle by bolting the u bolts on wrong right? Axle sits on the springs with a square portion so I don’t think a leaf spring swap (with no lift gain) would mess up the angles. At first I thought “oh maybe I overtightened 2 of the 4 u bolt nuts but I don’t think that would change anything really?