3.7 vs 4.0 Engine question

[demarpaint]

Hi and thanks in advance,


I recently bought an 08 Liberty for my wife and am very pleased with it so far. First time owning a Jeep. I see a lot of talk about putting the 4.0 engine in them (wish list I guess), anyway is there any real advantage other than HP and Torque? I understand more HP and torque is always a plus, but doesn't the 4.0 V6 use a timing belt? I was never a fan of engines with timing belts, and see it as a disadvantage. Just being curious since I am not familiar with Jeep/Chrysler products, and I am looking for opinions from people familiar with these engines.

Thanks and Happy New Year.

Frank D

 

[Dave]

The 3.7L is a chain driven OHC engine. (3 chains)....210hp with 235 torque

The 4.0 v6 also has 3 timing chains. But I think it has 24 valves and puts out something like 255hp and the torque is 265 or something like that. It is an aluminum block and heads. A little different than the 3.7L It is a whole different motor. And yes, timing chains are waaaaay better than belts as in some of the foreign stuff.

Dave

 

[demarpaint]

Thanks for clearing that up, thought the 4.0 had timing belts!

Frank D

 

[2003KJ]

Thanks for clearing that up, thought the 4.0 had timing belts!

Frank D

To my knowledge, not many new engines these days use timing belts any more. The lifespan of a timing chain is far more than that of a timing belt.

 

[indieaz]

To my knowledge, not many new engines these days use timing belts any more. The lifespan of a timing chain is far more than that of a timing belt.

Yah...why any manufacturer ever used a timing belt in any vehicle ever is beyond me. Timing belts=stupidest design ever.

 

[RamSport47]

The 3.7L is a chain driven OHC engine. (3 chains)....210hp with 235 torque

The 4.0 v6 also has 3 timing chains. But I think it has 24 valves and puts out something like 255hp and the torque is 265 or something like that. It is an aluminum block and heads. A little different than the 3.7L It is a whole different motor. And yes, timing chains are waaaaay better than belts as in some of the foreign stuff.

Dave

Some of the foreign stuff? aren't belts used in all of the foreign stuff?

 

[Dave]

Some of the foreign stuff? aren't belts used in all of the foreign stuff?

Ram.....I am not farmiliar with "all" of the foreign motors. Are all of them using belts instead of chains??

Dave

 

[k99jk99j]

Yah...why any manufacturer ever used a timing belt in any vehicle ever is beyond me. Timing belts=stupidest design ever.

one reason!: they have cheaper engineering and production costs. timing belts do not need an oiling system or a sealed timing cover! why do you think hyundias are so cheap? because they are still running majority of motors on timing belts!
i don't mind timing belts as long as the motor is not a valve cruncher.

 

[k99jk99j]

Ram.....I am not farmiliar with "all" of the foreign motors. Are all of them using belts instead of chains??

Dave

honda still uses timing belts alot! most of toyota's new motors are chain driven.

 

[midrider]

Does anyone know the difference between the 3.7 and the 4.0 on the 2008 liberty vs the Nitro motor? I'd like to find out how to beef up my 3.7 any ideas. I'm looking for a CAI or K&N filter any other thoughts?

 

[k99jk99j]

Does anyone know the difference between the 3.7 and the 4.0 on the 2008 liberty vs the Nitro motor?

the 3.7L is a 90 degree v-6 and the 4.0L is a 60 degree v-6. i think the 90 degree configurations produce more low end torque which is the reason they are in trucks and suv's. the 4.0l is only found in very few nitros (i believe only the r/t models). the majority of nitros have the 3.7L

 

[demarpaint]

So far I am pleased with the Liberty 3.7L, how do they hold up? I see mixed reviews. I own/owned the Ford 300 I6 and they go forever, the little Ford 3.0 V6's seem to last very long too. I end up keeping my vehicles until they beg to be junked!

Frank D

 

[_UnLiMiTeD_]

the 3.7 is a very popular motor being used right now and for the most part is pretty reliable, few people here and there have problems with them but every motor has a bad batch lol. Mine has been great so far, plenty of power. I know some say it lacks power but its a 4200+ lb vehicle with a v6 and it can pull of 16's in the quarter mile which is by no means something to write home about but deffinately not something to complain about in an suv i think.

 

[WalkGood]

I have no proof but have been told that the 4.0 Nitros are REALLY very bad on gas mileage. Even when driven steady on a long trip.

 

[Marlon_JB2]

I have no proof but have been told that the 4.0 Nitros are REALLY very bad on gas mileage. Even when driven steady on a long trip.

Most likely because people can't keep their foot out of them.

(The 4.0L Nitro really isn't even all that fast...)

 

[JeepINgeek]

but theyre supposed to be, Dodge marketed them as being a speedy suv

 

[bmanice]

i know you guys prob dont care, but it was brought up before...

you really cant classify "all" imports under the "timing belt" category. most manufacturers have motors that utilize both (audi, bmw, vw, porsche, etc). you are correct that the timing chain is a much more durable/efficient, design. just for an example, i had a 1988 bmw 535i that had a timing chain motor, lasted well past 250k miles, and on the other hand, there was an available motor that utilized a timing belt, that is well known to need to be changed around 100k, and its not too much fun. youll find that most timing belts are a 75k-100k recommended fix...


...again, you prob could careless lol, just felt like running my mouth a bit

cheers!

 

[Layston]

I used to drive an Eagle Vision (same as the first generation Chrysler Concorde/Dodge Intrepid) and it had a 3.5L 24 Valve V6. When it reached 100K I thought - okay, time to take it in for a new timing belt (yes it had a timing belt). I got to 103k and was on my way to work and thinking to myself - I have to call about that timing belt today when it BROKE!!! Luckily it was a non-interference engine and I just coasted to a stop.

I had a 2000 Dodge Intrepid (traded in for the Lib) and when I hit 90K I got the timing belt done just to be safe (same basic engine). So, even CHRYSLER puts timing belts on engines. I think that 3.5L engine is still in use in the 300C vehicles. Great engine, but remember to change that belt!

 

[_UnLiMiTeD_]

in the 300's and the charger