OHV vs SOHC

[bmerr98]

I have a feeling this has been covered ad nauseum, but I was wondering what people in the know thought of one or the other. I know the SOHC is rated at more HP, which is generally a good thing, but ratings aren't everything. Sometimes "improvements" don't translate from paper to reality.

So what's the scoop Ranger Buddies?

 

[JoshT]

I would guess that the SOHC makes better power at a higher RPM, and the OHV makes better torque at a lower RPM. This would really be better asked in the 4.0L forum though.

 

[Andy D]

The SOHC timing "cassettes" scare me. I have changed a timing set or 2, but a 1500$ cassette and an engine pull to replace ? I'm gonna stick with what I know.

 

[adsm08]

Yeah, the 4.0 SUCK isn't all it's cracked up to be on paper. Mileage is generally worse than an OHV, they do make extra power in a part of the band that will never be used unless you are in low range, and the amount isn't really significant.

The timing chains are a PITA as well. Book time to do them is roughly 25 hours. The issues with them were supposedly fixed by 2006 though.


Andy, I don't really understand your fear of the cassettes aside from the in depthness of replacing the rear one. If you lay it out next to the timing set for your OHV it really isn't any different, there are just two of them. The tensioners were different, and those were the big problem. They would wear and let the chains slack up and the chain slap would damage the guides. Replace those tenioner slugs every 75K or so and it would probably run forever.

 

[PlumCrazy]

OHV>SOHC

Sent from my XT907 using Tapatalk 2

 

[bigmark303]

The SOHC 4.0 doesnt really pull anymore than the OHV 4.0. Driven a few SOHC 4.0s and the extra hp is nice for passing other cars but the torque/pulling power seems to be the same.

As for cost and reliability the timing chain setups for OHC never last the life of the engine. You never see OHV engines replacing timing chain setups. Plus OHV is just dead simple to work on and maintain. Trucks dont need high rpm engines and thats all OHC can offer over an OHV.

 

[bmerr98]

I would guess that the SOHC makes better power at a higher RPM, and the OHV makes better torque at a lower RPM. This would really be better asked in the 4.0L forum though.

Sorry about misplacing the question. You're right though. If anyone cares to move the thread it won't hurt my feelings. Should have thought of that myself.

 

[exbass94]

SOHC makes more torque and HP than the OHV at ANY RPM, except below about 1700 RPM, where the OHV makes a lousy ~7 more ft-lbs. The SOHC makes its PEAK torque at about 3000 RPM. The OHV makes its peak at a lower RPM. When people hear that, they assume the SOHC has no torque down low. Not true. It has MORE torque than the OHV even at lower RPMs, and it STILL hasn't reached it's peak yet.

As an owner of both the 4.0 OHV and a SOHC, I much prefer the SOHC.

 

[PlumCrazy]

The SOHC has twice as many moving parts...like two timing chains, two cams, a counter shaft, counter shaft chain....no thanks.

Sent from my XT907 using Tapatalk 2

 

[bigmark303]

That chart is great for comparison. As far as torque its really a wash between the two. Another 15lb-ft is not a noticable difference. You will find between the two you still can and cant move the same loads.

As for HP the SOHC does keep up with traffic better, but thats all it does over the OHV. I wish they just revised the 4.0L OHV instead of designing a SOHC replacement that didnt offer much improvement torque wise. OHV is much better for truck applications all in my opinion of course

 

[85_Ranger4x4]

The SOHC has twice as many moving parts...like two timing chains, two cams, a counter shaft, counter shaft chain....no thanks.

You forgot the 12 pushrods and the 12 tick-o-matic lifters for the OHV in there...

I have no problems with OHC, the SOHC 4.0 IMO was a bandaid on an outdated engine that probably shouldn't have happened.

 

[adsm08]

SOHC makes more torque and HP than the OHV at ANY RPM, except below about 1700 RPM, where the OHV makes a lousy ~7 more ft-lbs. The SOHC makes its PEAK torque at about 3000 RPM. The OHV makes its peak at a lower RPM. When people hear that, they assume the SOHC has no torque down low. Not true. It has MORE torque than the OHV even at lower RPMs, and it STILL hasn't reached it's peak yet.

As an owner of both the 4.0 OHV and a SOHC, I much prefer the SOHC.

Yeah. Look really closely at the numbers on the bottom of that chart.

I drove like an idiot the first 8 years I had my license. I still drive like an idiot sometimes. Almost every vehicle I have owned had a tach in it. I can count on one hand the number of times in 11 years that I have had an engine spinning at 4000 RPM or higher in gear. I rarely get it above 2500, even my 2.9.

Explain to me again how having more power in a part of the RPM band that isn't used after first gear is helpful in anything but a dedicated tow rig.

 

[PlumCrazy]

Id rather listen to a lifter tick until warms up rather than a timing chain slap until it blows up....

Sent from my XT907 using Tapatalk 2

 

[Scrambler82]

Are you planning on buying a Ranger and thinking on what motor to look for, IMHO, find a truck you like either engines will work OK. Yes the SOHC may make more power but the older Push Rod style 4.0 will deliver when and if needed.

I have a feeling this has been covered ad nauseum

Latin wow are we coming up in style; I had to look that one up, nice use of words.

I would guess that the SOHC makes better power at a higher RPM, and the OHV makes better torque at a lower RPM. This would really be better asked in the 4.0L forum though.

OHV>SOHC

OHV = Valves In Head on top of the engine and both engines have them. Correct terms might be… SOHC = Single Overhead Cam; Standard 4.0 = A Push Rod Engine.
But to call one an OHV and not the other is not correct.

Id rather listen to a lifter tick until it warms up rather than a timing chain slap until it blows up...

Both situations are not wanted but the older 4.0 Push Rod Engine might be a little easier to work on and produce decent power for most people.

There are power add ons that can give you good power but as everything else at what price.
New Cam, new exhaust headers, new Throttle body and air intake system, where do you want to go and how much do you want to pay.

Don’t let the engine stop you from buying the truck you like, they both work work out OK.

Just my 2 cents !

 

[6.2]

Yeah. Look really closely at the numbers on the bottom of that chart.

I drove like an idiot the first 8 years I had my license. I still drive like an idiot sometimes. Almost every vehicle I have owned had a tach in it. I can count on one hand the number of times in 11 years that I have had an engine spinning at 4000 RPM or higher in gear. I rarely get it above 2500, even my 2.9.

Explain to me again how having more power in a part of the RPM band that isn't used after first gear is helpful in anything but a dedicated tow rig.

You're idea of driving like an idiot sounds pretty tame then lol. I go over 4k rpm all the time. In all the gears.