73 mph M1008

[Monkeyboyarmy]

Brought a cucv back from Pontiac Mi yesterday. Got it up to 73 mph. That's pretty good aint it?

 

[porkysplace]

Brought a cucv back from Pontiac Mi yesterday. Got it up to 73 mph. That's pretty good aint it?

It depends on if you have a spare motor laying around.

 

[doghead]

Must have been on a trailer.

 

[cucvrus]

Not to fight. But I drive these trucks at 75-80 all the time. I am serious. I have been doing it for years. I never blew one up. I drove them cross country with the stock 4:56 gears pulling another CUCV on the tow bar. Did all day and night several times. I never had any issues. I get some throttle surge when I let up at 80 but that is normal according to the GM shop manual. I change my oil every 2K and keep them serviced well. I towed an M1010 to north west Canada back in the late 90's and drove my M1028 6500 miles in 10 days. I had the oil changed twice at a truck stop parking lot. It never was low on oil and I was getting about 16 MPG average over the whole trip. I just never gave it any thought. I may just be lucky. it always reminds of my boat when I have it planed out. Just keeps running and running.

 

[Monkeyboyarmy]

Must have been on a trailer.

No no

 

[Triple C]

This would probably get more traction in the CUCV forum?

 

[Swamp Donkey]

Yeah...you're definitely not hitting 73 mph in the 5 ton forum...lol.

 

[dawico]

Brought a cucv back from Pontiac Mi yesterday. Got it up to 73 mph. That's pretty good aint it?

Very good for a 5 ton and up CUCV. (Why is this posted here?)

 

[Monkeyboyarmy]

 

[doghead]

Wow, it came from the "rust belt"?

Armored rear wheel wells?

 

[FMJ]

Wow, it came from the "rust belt"?

Armored rear wheel wells?

Thats for driving around in downtown Detroit. . . .

 

[Monkeyboyarmy]

Sorta something like that. They've really aged it in the past 5 months. This is what it looked like in July.

 

[Westech]

73 mph in a 915?

Do you know what happens to a Transfer case with 4.56 gears spinning at 3600 RPM? They get very very hot.
An M1008 traveling at 73 mph, the engine is spinning past the governed speed of 3600 RPM. I do not think you traveled cross country with the engine bouncing off the governor for 1000's of miles.

Kinda sounds like a fish story to me.

 

[Monkeyboyarmy]

Driveshaft was disconnected. 1100-20s and 2200 rpm. Sure does use some fuel though.

 

[Iceman3005]

Here are your RPM's at given speeds in 3rd gear (ratio 1:1 motor/trans) with 4.56's gears and 32 inch tires, the governor is supposed to start letting you know it is there around the 3400rpm mark:

3600=75.6
3500=73.06
3400=70.98
3300=68.89
3200=66.8
3100=64.72
3000=62.63
2900=60.54
2800=58.45
2700=56.37
2600=54.28
2500=52.19
2400=50.11
2300=48.02
2200=45.92
2100=43.84
2000=41.75
1900=39.67
1800=37.57
1700=35.49
1600=33.4
1500=31.31

So you can see hitting 80 is impossible, and 75 is hitting the governor. I think if you hit 73 then that is probably tops. For a cucv to get 16 mpg at 80 mph is impossible, before I did my 700r4 swap only driving 50 to 55 mph back and forth to work 30 miles one way, I could only get 14-15 mpg. After the swap, doing 50-55 to work and back I could get 18-20 mpg. If I did any thing over 60 mph I would only get 16 or less the faster I went.

 

[Iceman3005]

here is the online rpm, gear, tire, speed calculator I used. http://www.angelfire.com/fl/procrastination/rear.html

 

[Keith_J]

I've done 70 MPH in my 1031 SECM. But I had swapped the harmonic damper with a brand new one.

If 3600 rpm is bad for the engine, they should have made the redline 3400 or whatever is safe. The only thing 3600 RPM does is tests the cooling system. Indirect injected engines dump lots of heat to the cooling system as the flame jets out of the cylinder head combustion chamber. Direct injected engines have issues with piston temperature.

 

[CUCVLOVER]

Are you saying that you drove a stock m1008 ?

I wouldn't do that my dad drove mine back from way out the other side of little rock Arkansas And if we broke 65 mph I could tell the truck didn't like it.
I put a tachometer on it and at 55 its at about 2600 rpm.

 

[Monkeyboyarmy]

Guess I just opened up a can of worms.

 

[CUCVLOVER]

What was it like in a cucv at that speed?