2.8 Or 2.5 Which Would You Choose

[coyote kid]

which would you prefer in a mj or xj ? I   would go 2.5

[Automan2164]

2.8L All day long:

 

[coyote kid]

For what reasons just curious

[Automan2164]

Turbo diesel. #1.

 

Rob

[coyote kid]

How good was the 2.8 that came in the 86 mj's and xj's

[carnuck]

Late '86 ones were internal balanced and OK. Earlier ones were external with skinny rod bearings that died easy. I'd go 2.5 with TBI or MPFI from a TJ. More power than 2.8 and easier to work on.

[onlyinajeep726]

Turbo diesel. #1.

 

Rob

 

I think the OP was talking about the GM2.8L lol.  In which case, I'd go 2.5L hands down.  My '86 will have a 4.0 once I'm done with everything haha. :yes:

[88whitemanche]

2.5! Torquey, strong, and fuel efficient

[JeepcoMJ]

the 86 2.8 is not internally balanced FYI

 

 

In no way, shape, or form will I ever even get back in any vehicle that has a 2.8l v6 and start it. Any 2.8 I get will immediately get a motor swap, whether it's in running condition or not. This also goes for most things gm, save buick 3800 powered and early 06 duramax. Won't ever ride in anything with a 6.5TD again.

 

 

I'm with Rob, 2.8 VM FTW

[Automan2164]

 

 

 

Turbo diesel. #1.

 

Rob

I think the OP was talking about the GM2.8L lol. In which case, I'd go 2.5L hands down. My '86 will have a 4.0 once I'm done with everything haha. :yes:

OP never specified. Devil is in the details.

 

Rob ;)

[yxmj]

2.5 all day long......................Find me a 2.8 with 300,000+ miles that has not been rebuilt

[onlyinajeep726]

 

 

 

 

Turbo diesel. #1.

 

Rob

I think the OP was talking about the GM2.8L lol. In which case, I'd go 2.5L hands down. My '86 will have a 4.0 once I'm done with everything haha. :yes:

OP never specified. Devil is in the details.

 

Rob ;)

 

This is true ha.  VM > GM.

[BebopComanche]

2.5! Torquey, strong, and fuel efficient

Torquey enough to, say, pull stranded people out of the snow in the winter possibly? I've been wondering how well it performs compared to its larger option.

[carnuck]

 

2.5! Torquey, strong, and fuel efficient

Torquey enough to, say, pull stranded people out of the snow in the winter possibly? I've been wondering how well it performs compared to its larger option.

 

I drove to Ouray, CO with my Comanche weighing in at 6500lbs (canopy, tools, spare parts, 3 spare tires, food, water and 3 adults). That was through the mountains at minimum speed of 55 mph too. In low range the TBI 2.5L had even more power to spare. The turd point hate? Not so much!

[BebopComanche]

 

 

2.5! Torquey, strong, and fuel efficient

Torquey enough to, say, pull stranded people out of the snow in the winter possibly? I've been wondering how well it performs compared to its larger option.

 

I drove to Ouray, CO with my Comanche weighing in at 6500lbs (canopy, tools, spare parts, 3 spare tires, food, water and 3 adults). That was through the mountains at minimum speed of 55 mph too. In low range the TBI 2.5L had even more power to spare. The turd point hate? Not so much!

Er, I probably should have said 4.0 instead of larger cousin. But this is still good information that I was lacking, so thank you.

[Minuit]

With the 4.0 you would never have to worry about having enough power to do anything a light truck has any business doing. The 2.5 is gutless compared to the 4.0 but still a perfectly good motor and just as reliable. The turdy eight hundred? 2 more cylinders to feed voraciously but somehow less power. The 2.8 will make a 2.5's mileage look excellent - but get the 4.0 if you get the chance.

 

And you better like vacuum lines if you have a 2.8.

 

[carnuck]

With my shortbox 4.0L AW4, 3.73 gears and 33" tires I hauled a Metric Tonne (yes, 2200 lbs) up a VERY steep hill from a stand still at the bottom and I was able to hit 35 (speed limit) before the top without using low range.

[mpace6a]

With the 4.0 you would never have to worry about having enough power to do anything a light truck has any business doing. The 2.5 is gutless compared to the 4.0 but still a perfectly good motor and just as reliable. The turdy eight hundred? 2 more cylinders to feed voraciously but somehow less power. The 2.8 will make a 2.5's mileage look excellent - but get the 4.0 if you get the chance. And you better like vacuum lines if you have a 2.8.

My 2.8 averages 17 between city/highway driving.Granted, its gutless. Can do 80 downhill...85 if you add in a tailwind. But i can keep up with everyone on the highway. Not necessarily defending the 2.8, just don't want to discourage someone from an MJ solely because of it. With a time and mechanical inclination you can remove most of the vacuum and have an alright truck.

 

 

2.5! Torquey, strong, and fuel efficient

Torquey enough to, say, pull stranded people out of the snow in the winter possibly? I've been wondering how well it performs compared to its larger option.

Dunno about the snow, but I pulled my brothers XJ out of a pit he drove down into, and tried to climb back out of the 10' high sides. Buried his jeep up to the axles and my 2.8/ax5 pulled him out no problem, in 4high because i don't have 4lo

[mnkyboy]

2.5l will pull pretty good, traction is a bigger issue then power.

 

I've yarded several full size trucks out of mud and snow with my 2.5l MJ. I have also pulled out a forklift that was stuck in mud past its axles.

[87Warrior]

I like to compare the 2.5 TBI to the 4.2 Carter carbed motor in the YJ. They seem to drive the same and have about the same power output. The difference? The 2.5 will get 2X the fuel economy and will continue to run without headache.

 

I can't insult the 2.8 as I've never had the (mis)pleasure of owning one. But I am quite happy with the 2.5 in my '86. It is certainly not a 4.0, but can still hold 75mph through the Flint Hills on the interstate here in KS. 

[Eagle]

2.5L all the way.

 

The 2.8L for the XJ (and then the MJ) was strictly an afterthought. The XJ was introduced in late 1983 as a 1984 model year vehicle. It was designed around the 2.5L engine. Then Jeep realized that other vehicles they would be competing against were available with a V6, so they decided they needed a V6 option and cut what they thought was a deal with GM for the 2.8L -- which GM had given up on at that point.

 

It was a deal all right -- for GM.

[FrankTheDog]

The early XJ's were a product of that time. In the early 80's it was thought we were going to be running out of gas soon.

When I got my license in 1980 gas was a $1.30 or so a gallon.

I was making $3.00 an hour. I don't think it went over a $1.75 until after 2001

In 1999 it was around $1.00 a gallon. That's probably why they had such small engines in the beginning.

[carnuck]

I hauled another 2200 lb load of gravel yesterday. To my cabin this time (10 miles of Hwy 2 and 4.5 miles of pot holed driveway)

[mvusse]

2.5.

 

More HP, comparable torque and way better fuel economy.

[airspeed]

2.5 is much simpler lay out for fuel and emissions systems.  The 2.8 is a vacuum nightmare.

 

2.5 has better fuel economy!!