6.2 or 6.5

[biggdadd58]

I realize that I am still learning about these things and apologize for all the questions. What are the pros and cons between these 2 engines? I would like to be able to drive at least 60 mph with what I purchase. I am looking for advice before looking to purchase. If you have any input, please put it out there. Or if you would be willing to talk on the phone, please message.

 

[porkysplace]

I realize that I am still learning about these things and apologize for all the questions. What are the pros and cons between these 2 engines? I would like to be able to drive at least 60 mph with what I purchase. I am looking for advice before looking to purchase. If you have any input, please put it out there. Or if you would be willing to talk on the phone, please message.

You probably should pick 1 of your threads on the same thing instead of cross-posting the same thing with different titles and keep all the information in 1 thread.

Difference between M988 and the M998A1



[h=1]94 hmmwv[/h]
[h=1]2 Questions: Block Heaters, and 12V/24V Jump Starting[/h]
[h=1]Mileage[/h]



Transmission Swap

 

[biggdadd58]

Not sure how or if posting in the same thread would get questions answered. The reason for this one was to be able to hear the pros and cons between both engine combinations from actual owners.

 

[98G]

If you want a sustained 60mph then you want a 4spd transmission. Neither the 6.2 nor the 6.5 will be happy at 60 for long with the 3spd behind it.

Personally I don't see a huge difference between the 6.2 and the 6.5.

GEP engines are to be preferred, but this is well down the list of priorities. Well below overall condition.

 

[biggdadd58]

What is a GEP engine?

If you want a sustained 60mph then you want a 4spd transmission. Neither the 6.2 nor the 6.5 will be happy at 60 for long with the 3spd behind it.

Personally I don't see a huge difference between the 6.2 and the 6.5.

GEP engines are to be preferred, but this is well down the list of priorities. Well below overall condition.

 

[ken]

A GEP engine is a engine made by General Engine Products. It is a higher quality engine than the GM version.

What is a GEP engine?

 

[83scrambler]

How do you determine if you have a GEP engine or GM?

 

[ken]

Sticker on the drivers side valve cover is the easiest way for the untrained eye. It will sat GEP or if it is a GM it will say Detroit Diesel

 

[biggdadd58]

Sticker on the drivers side valve cover is the easiest way for the untrained eye. It will sat GEP or if it is a GM it will say Detroit Diesel

Thank you.

 

[2deuce]

Maybe this has been discussed already, but did GEP make both engines? and if they made the 6.2 were they in the CUCV too? How were the GEP engines better? Thanks

 

[gimpyrobb]

No.

GEP made 6.5s only.

 

[papakb]

My understanding is that GM (actually Detroit Diesel) made the 6.2L engines from 1982 until 1993 to put behind their trucks and AMG adapted it for use in the HMMWV. When they needed more power GM upped the displacement to 6.5L and built them for a much shorter period than the 6.2's. When they discontinued production AMG bought the production rights and produced them under the General Engine Products name and corrected all the manufacturing issues GM refused to address.

The easiest way to identify the GEP engines is by looking at the bolt that retains the tachometer/ STE/Ice drive in the back of the block valley. If the hold down bolt is on the right side it is a GEP engine and the "right one" for the trucks. If the hold down bolt is to the left of the drive it's the older 6.2L engine.

 

[infidel got me]

I've owned both the 6.2 and the 6.5 and really couldn't tell any difference between the two.