Purchasing M1009, Have a Few Questions

[dbl505]

Hey guys, newbie here. I am in the process of finalizing a purchase of a 1984 M1009. According to the owner, the vehicle only has 41k miles on it and it sure looks like it is in great condition. I was hoping someone on this site could tell me what to look for when buying this vehicle and the things to immediately do after I purchase the vehicle to make it run stronger. Since the vehicle comes with no air conditioning, would it be possible to take the AC unit out of a civilian k5 blazer and transfer it to the m1009? Also, is it possible to run a fair amount of 12v accessories since the vehicle has a 24v system? Thanks for any answers, I'm new to the world of MVs.

 

[Bighorn]

If it is totally stock, only your starter is 24 volt.
Everything else runs on 12 volts.

Do the Doghead starter relay conversion.
The stock starter relay is poor quality and has a history of sticking which can burn up your starter.

Go through the glow plug system.
There is a relay upgrade for that as well as a better glow plug control card available.

Fuel pumps are a known weakness. The fuel pump is on the passenger side of the block and it just pumps fuel at low pressure up to the injection pump.
Might be a good idea to replace it due to age alone.

The 10 bolt rear gov lock axle has a few weaknesses.
The axle bearings ride directly on the axle shafts. Don't assume because of low mileage that there is not a great deal of wear there.
Jack up the rear end and see if there is play.
Put a finger along the gap between the brake drum and backer plate while an assistant lifts on the wheel.

The rear stud shock mounts have a habit of becoming loose.
Grab the top of the shock and twist to see it it is loose.

All Chevy Blazers prior to 1987 tend to develop frame cracks under or near the steering box.
Have someone turn the steering wheel while you observe the frame under the steering box.
If there are cracks, you'll see them.
There are kits( to repair them and a brace (Off road Design) to reinforce the area if you plan on tires 33" or larger.

Headlight wiring connections are notorious for becoming corroded resulting inone or more dim lights.

On a truck this old all grounds; frame to battery, frame to frame, everywhere you find them, should be removed and cleaned.

Brake calipers can become sticky with age.
Easily replaced, same as civilian version.

The rear gov lock is not known for strength with larger than stock tires or when used off road.

The stock 3.08 ratio gearing is very tall and will cause the turbo 400 transmission to slip if you try and tow heavy things at high speeds uphill.

The NP 208 transfer case is excellent as long as you keep the fluid fresh.
It takes Automatic Transmission Fluid NOT GEAR OIL.

The ac compressor would need to be swapped from a civilian 6.2 equipped truck or blazer but since you have an extra alternator already occupying that spot, it would take some doing.
You would need the interior evap core, the radiator mounted condenser, all the hoses, the receiver dryer, the compressor and all the brackets.
I don't know man.
I think I would just crack a window instead.

 

[dougco1]

If it is totally stock, only your starter is 24 volt.
Everything else runs on 12 volts.

Do the Doghead starter relay conversion.
The stock starter relay is poor quality and has a history of sticking which can burn up your starter.

Go through the glow plug system.
There is a relay upgrade for that as well as a better glow plug control card available.

Fuel pumps are a known weakness. The fuel pump is on the passenger side of the block and it just pumps fuel at low pressure up to the injection pump.
Might be a good idea to replace it due to age alone.

The 10 bolt rear gov lock axle has a few weaknesses.
The axle bearings ride directly on the axle shafts. Don't assume because of low mileage that there is not a great deal of wear there.
Jack up the rear end and see if there is play.
Put a finger along the gap between the brake drum and backer plate while an assistant lifts on the wheel.

The rear stud shock mounts have a habit of becoming loose.
Grab the top of the shock and twist to see it it is loose.

All Chevy Blazers prior to 1987 tend to develop frame cracks under or near the steering box.
Have someone turn the steering wheel while you observe the frame under the steering box.
If there are cracks, you'll see them.
There are kits( to repair them and a brace (Off road Design) to reinforce the area if you plan on tires 33" or larger.

Headlight wiring connections are notorious for becoming corroded resulting inone or more dim lights.

On a truck this old all grounds; frame to battery, frame to frame, everywhere you find them, should be removed and cleaned.

Brake calipers can become sticky with age.
Easily replaced, same as civilian version.

The rear gov lock is not known for strength with larger than stock tires or when used off road.

The stock 3.08 ratio gearing is very tall and will cause the turbo 400 transmission to slip if you try and tow heavy things at high speeds uphill.

The NP 208 transfer case is excellent as long as you keep the fluid fresh.
It takes Automatic Transmission Fluid NOT GEAR OIL.

The ac compressor would need to be swapped from a civilian 6.2 equipped truck or blazer but since you have an extra alternator already occupying that spot, it would take some doing.
You would need the interior evap core, the radiator mounted condenser, all the hoses, the receiver dryer, the compressor and all the brackets.
I don't know man.
I think I would just crack a window instead.

I've owned my 1009 for 6 years now and after reading Bighorn's "watch-out list" I'm scared. Maybe I should give mine away. I think you have the opportunity to enjoy a good old truck and not worry about things. Yes its 33 years old and things will break but it has lasted this long and with the proper care will last a lot longer. Just take it one repair at a time, try to keep it stock and enjoy your new ride.

 

[cucvrus]

Yes after 22 years of owning the same M1009 I would tend to think they are fine the way they came from the factory. After all the hard use and abuse at times I never broke a frame at the steering box. or had any of the issues that are listed. The broken/cracked frame many times comes from resistance, (bad axle joints) Bigger then stock tires, snow plows, or loose bolts on the steering box.
#1 on my list would be new group 31 batteries. That will almost eliminate any electrical problems associated with the so called poor quality starter relay. #2Making sure the glow plugs are good so you don't have to crank it till the batteries are weak and the starter worn down and tired. The stock glow plug system worked this long. If it still works the glow plug card is doing its job. The less you mess with the easier it is to ask here and others for help.
#3 I would take it one day at a time. Brakes I agree. I would put a rebuilt master cylinder, calipers, rear wheel cylinders on it. They are full of crud. But other then that I would tend to think you should have a good vehicle. These are not vehicles for a guy to buy that has no mechanical experience. Unless you have deep pockets. Most guys can fix most things themselves with some help. But keep in mind 34 year old vehicles have 34 year old vehicle problems. If you are OK with that I say buy it. Have fun with it and enjoy. Good Luck. I hope you make the deal.

 

[Bighorn]

Ha ha!
Yea, I did not intend my laundry list to sound like doom and gloom.
I love these trucks.
Own 2 of them now.

These Internet forums are great but sometimes it is hard for me to relate the context of my words.

I was just telling him what to look for.
Not saying "the sky is falling".
Yes, buy that truck and love it.

 

[dbl505]

If it is totally stock, only your starter is 24 volt.
Everything else runs on 12 volts.

Do the Doghead starter relay conversion.
The stock starter relay is poor quality and has a history of sticking which can burn up your starter.

Go through the glow plug system.
There is a relay upgrade for that as well as a better glow plug control card available.

Fuel pumps are a known weakness. The fuel pump is on the passenger side of the block and it just pumps fuel at low pressure up to the injection pump.
Might be a good idea to replace it due to age alone.

The 10 bolt rear gov lock axle has a few weaknesses.
The axle bearings ride directly on the axle shafts. Don't assume because of low mileage that there is not a great deal of wear there.
Jack up the rear end and see if there is play.
Put a finger along the gap between the brake drum and backer plate while an assistant lifts on the wheel.

The rear stud shock mounts have a habit of becoming loose.
Grab the top of the shock and twist to see it it is loose.

All Chevy Blazers prior to 1987 tend to develop frame cracks under or near the steering box.
Have someone turn the steering wheel while you observe the frame under the steering box.
If there are cracks, you'll see them.
There are kits( to repair them and a brace (Off road Design) to reinforce the area if you plan on tires 33" or larger.

Headlight wiring connections are notorious for becoming corroded resulting inone or more dim lights.

On a truck this old all grounds; frame to battery, frame to frame, everywhere you find them, should be removed and cleaned.

Brake calipers can become sticky with age.
Easily replaced, same as civilian version.

The rear gov lock is not known for strength with larger than stock tires or when used off road.

The stock 3.08 ratio gearing is very tall and will cause the turbo 400 transmission to slip if you try and tow heavy things at high speeds uphill.

The NP 208 transfer case is excellent as long as you keep the fluid fresh.
It takes Automatic Transmission Fluid NOT GEAR OIL.

The ac compressor would need to be swapped from a civilian 6.2 equipped truck or blazer but since you have an extra alternator already occupying that spot, it would take some doing.
You would need the interior evap core, the radiator mounted condenser, all the hoses, the receiver dryer, the compressor and all the brackets.
I don't know man.
I think I would just crack a window instead.

Thanks for the reply, definitely will be looking for this when i get to check the vehicle out in person. The biggest size tires i would want to run is 33's, but i have heard a lot of things about running 33's on stock gearing. Is it really a bad thing to run that size tires with the 3.08s? Also, is there a way to get rid of the gov lock without buying a whole new axle? One last question I have is if running a 12v stereo is bad for the batteries since they are wired in succession to be 24v. Most posts i have read say to install the stereo through the fusebox, but if theres a way to do it directly to the battery i would rather go that route.

 

[Bighorn]

I ran my 1984 K5 Blazer with 10 bolt axles and 3.08 gears for 3 years.
No it isn't bad.
Just slow off the line.
Towing is painful up hills and you'll be in second gear a lot if the hills are steep.
If you plan to wheel the truck hard, the 10 bolt axle shafts and that gov lock are not going to last.
I've broken an axle shaft and the wheel, brake drum, and remaining axle shaft comes right out of the housing.
There is a reason the gov lock is called a grenade lock.
It allows 100 rpm difference in wheel spin side to side before it locks.
With big tires this can be violent enough to break the carrier.
Again.
This may not be a problem for you.
Many people never have a problem with their stock setup.
If you put 33's on that truck and wheel it hard, you will break things.
The radio is not a problem.
Yes, you can swap a different carrier into that 10 bolt and swap up to 30 spline shafts.
Many people do that.
Many people swap up to dana 60 front 14 bolt rear.
If you are going to wheel it hard, I and many others, recommend the latter.

 

[dbl505]

I ran my 1984 K5 Blazer with 10 bolt axles and 3.08 gears for 3 years.
No it isn't bad.
Just slow off the line.
Towing is painful up hills and you'll be in second gear a lot if the hills are steep.
If you plan to wheel the truck hard, the 10 bolt axle shafts and that gov lock are not going to last.
I've broken an axle shaft and the wheel, brake drum, and remaining axle shaft comes right out of the housing.
There is a reason the gov lock is called a grenade lock.
It allows 100 rpm difference in wheel spin side to side before it locks.
With big tires this can be violent enough to break the carrier.
Again.
This may not be a problem for you.
Many people never have a problem with their stock setup.
If you put 33's on that truck and wheel it hard, you will break things.
The radio is not a problem.
Yes, you can swap a different carrier into that 10 bolt and swap up to 30 spline shafts.
Many people do that.
Many people swap up to dana 60 front 14 bolt rear.
If you are going to wheel it hard, I and many others, recommend the latter.

I was definitely considering getting an m1008 just for the axles, but i have never swapped something that large in a vehicle so that's the only thing that worries me about going down that path.

 

[Mainsail]

The biggest size tires i would want to run is 33's, but i have heard a lot of things about running 33's on stock gearing. Is it really a bad thing to run that size tires with the 3.08s? Also, is there a way to get rid of the gov lock without buying a whole new axle?

Why 33s? Do you think you need them or are you going for a 'look'? The 31x10½ tires are stock for the M1009, and you'll have few problems (if any) keeping it stock. Not a criticism just asking. I'm been driving mine daily for five years and have done only PM and minor maintenance.

One last question I have is if running a 12v stereo is bad for the batteries since they are wired in succession to be 24v. Most posts i have read say to install the stereo through the fusebox, but if theres a way to do it directly to the battery i would rather go that route.

Like the diffs, treat the fusebox kindly. The truck is old and wiring in an aux fusebox is easy work. You can run it off a relay from the wiper circuit if you want key-on power only.

Also, Bighorn mentioned that only the starter is 24v, but he left out the glow plugs which run off the 24v system.

Do the doghead relay mod the day you get it. Do NOT wait for that one.

 

[Bighorn]

Again, this only applies if you intend to wheel your truck hard.
I wheeled my stocker for several years before I broke the axle. Your mileage may vary.

 

[dbl505]

Why 33s? Do you think you need them or are you going for a 'look'? The 31x10½ tires are stock for the M1009, and you'll have few problems (if any) keeping it stock. Not a criticism just asking. I'm been driving mine daily for five years and have done only PM and minor maintenance.

Like the diffs, treat the fusebox kindly. The truck is old and wiring in an aux fusebox is easy work. You can run it off a relay from the wiper circuit if you want key-on power only.

Also, Bighorn mentioned that only the starter is 24v, but he left out the glow plugs which run off the 24v system.

Do the doghead relay mod the day you get it. Do NOT wait for that one.

It's only for a look, I do not plan on doing any off roading with the truck. Where do i find the parts for the doghead relay mod?

 

[Bighorn]

Just search Doghead Relay Mod here on Steel Soldiers.
Plenty of info.
Thanks for correction on glow plugs.

 

[Drock]

Well for the past 3 years my M1028 has bin my (ONLY) transportation for me, and my furniture business. I drive approximately 2000 miles per month all over the state of GA. Including everything from grocery shopping, hauling 2000 LBS of steel, or hauling my furniture. I wanted an old truck to tinker with,and not worry about scratching. I think the CUCV was an excellent choice! It has a habit of continuing to run & drive even when it's broken LOL! . Agree with earlier posts, Start with getting the glow plug system working correctly. Then replace everything with the braking system! make sure to use DOT5 fluid (Stainless steel brakes) sells the cheapest I've found. The main problem you'll find with these trucks is that they've sat for 30+ years. Every gasket & anything rubber is dry rotted and WILL eventually fail or leak. Mine had 20,000 miles on it when I bought it. I think I spent around $2000.00 in parts to be able to start driving it daily (not including tires).