Mack R Model W/ V8

[Warpman89]

hello, i am curious is there anyway to tell if a r model has a v8 without opening the hood? are there any exterior differences? i have noticed that some r model's have a longer hood, is that only if they have a v8? thanks

[ThaddeusW]

hello, i am curious is there anyway to tell if a r model has a v8 without opening the hood? are there any exterior differences? i have noticed that some r model's have a longer hood, is that only if they have a v8? thanks

Hi there,

The long hood R models were the R700 or RS700. Those models could have a Mack in line 6 cylinder, Mack V8, Cummins, CAT or Detroit Diesel. If it had a Mack V8 it would (should) have a V8 badge on the side. The V8 badge was only for the Mack V8 so a Detroit Diesel 8V71 or Cummins 903 V8 would not have a V8 badge. Other than that there isnt much else from the outside to tell what was under the hood. If you had the exact model number eg. RS797LST.

Lets break down the Model number RS797LST:

R - R model

S - Steel frame (this is a "western" Mack model designation, for Mack's made in the Hayward, CA plant. L would denote an aluminum frame)

7 - Not 100% sure but pretty much means a longer hood

97 - Engine code, 97 is for a Mack ENDT866 (I think)

L - Light weight components like Aluminum doors.

S - Six wheel chassis

T - Tractor

[Rob]

Close Thad: The "L" in the designation denotes lightweight components such as spring hangers, fuel tanks, rear axle carriers, front hubs and several other little items, or none. It was really up to the person ordering the truck.

As per your analogy:

RS= steel frame

RL=aluminum frame

"7"= longer hood

"XX" = engine callout numbers denoting which engine is original equipment; (97 was an ENDT866 Thermodyne, 95 was an ENDT865 Maxidyne)

"L" = lightweight components as mentioned

"S" six wheel chassis

"T" tractor configuration

"XXXXX" serial number of chassis prior to 1980

Both of my "RL700LST" series tractors have many of the aluminum components.

Rob

[B61TENDT711]

Has a V-8 ? was it any good ? . . .

Mike

Edited October 27, 2009 by B61TENDT711

[Rob]

I can't tell you from first hand experience as I've never been a truck driver that has used one of the V8's produced by Mack. I have been told by many they were real "powerhouses" in their heyday, but changing emmisions laws in this country was to their demise in production.

Parts are getting scarce and therfore expensive to acquire as of late.

Rob

[B61TENDT711]

Sounds as tho it held up alright. . .

Mike

[other dog]

I can't tell you from first hand experience as I've never been a truck driver that has used one of the V8's produced by Mack.

I have been told by many they were real "powerhouses" in their heyday, but changing emmisions laws in this country was to their demise in production.

Parts are getting scarce and therfore expensive to acquire as of late.

Rob

Me either, but I always wanted to be.

And they are - I've had my doors blown off many times by V8 Macks.

There's nothing like a V8 Mack with a straight pipe.

[Rob]

Me either, but I always wanted to be. I've had my doors blown off many times by V8 Macks.

There's nothing like a V8 Mack with a straight pipe.

Don't really need a muffler as the noise is not objectionable out the stack. It is actually quite quiet.

Does sound really good under an overpass, or between buildings.

Rob

[other dog]

Don't really need a muffler as the noise is not objectionable out the stack. It is actually quite quiet.

Does sound really good under an overpass, going through a tunnel, or between buildings.

Rob

they definately have a sound all their own. I love to hear one running.

[Lmackattack]

As far as looking at the outside its hard to tell if it has a v8 or not

the early R600 models had an option for V8s then in the late 60s I think they only came in the R700 or RS/RL700 models. If the truck had a V8 fromthe factory it would have had a V8 emblem on the hood. on thing to look for is if it has a single stack. alot of the bigger V8s used a 5" exhaust where the Inline 6 had a 4".if it had twin stacks it will be harder to tell as you can run 5" from the turbo to the T pipe under the cab and 4" from the T-pipe to the mufflers. The Stock E9 V8 macks were pretty quiet even without mifflers. I have driven a 440 and 500. the ones I drove spun to 1900RPM and pulled pretty good. you could keep up with new trucks of the same HP all day. the company I drive for had a 2002 pete with a 550 cat and the 440 mack would walk on it up to about 60MPH.

[other dog]

As far as looking at the outside its hard to tell if it has a v8 or not

the early R600 models had an option for V8s then in the late 60s I think they only came in the R700 or RS/RL700 models. If the truck had a V8 fromthe factory it would have had a V8 emblem on the hood. on thing to look for is if it has a single stack. alot of the bigger V8s used a 5" exhaust where the Inline 6 had a 4".if it had twin stacks it will be harder to tell as you can run 5" from the turbo to the T pipe under the cab and 4" from the T-pipe to the mufflers. The Stock E9 V8 macks were pretty quiet even without mifflers. I have driven a 440 and 500. the ones I drove spun to 1900RPM and pulled pretty good. you could keep up with new trucks of the same HP all day. the company I drive for had a 2002 pete with a 550 cat and the 440 mack would walk on it up to about 60MPH.

I don't know anything about the E9's, but the ol' 325 and especially the 375s were a "hawse" in their day as they say.