ECO Hubs Who needs 3:07 gears?

[shawnspeak]

Am no authority on such things, but isn't the max input HP/Torque rating of the transmission 330/875? Seems that if the eco-hubs make better (or full) use of the torque converter, as has been previously discussed, then flashing the engine beyond these ratings might have some effect on transmission longevity.

 

[GeneralDisorder]

Am no authority on such things, but isn't the max input HP/Torque rating of the transmission 330/875? Seems that if the eco-hubs make better (or full) use of the torque converter, as has been previously discussed, then flashing the engine beyond these ratings might have some effect on transmission longevity.

If 40 HP and 56 Ft/lbs breaks a transmission on a truck that is 1/4 of the weight of an A1P2 M1089 wrecker fully loaded then it was going to break anyway. The transmission is grossly underrated in this application for civilian uses.

And everyone should be much more concerned about the transfer case C6 thrust bearing than the HP/TQ rating that has proven to be more of a suggestion over the last 30 years operating these trucks. I'm hopeful that spinning the transmission at half it's normal speed with the ECO hubs and using quality synthetic Dexron will ensure that ugly failure doesn't arise for me.

 

[serpico760]

If you want an M1079 then wait for one. That's what I did. It's worth it in my opinion.

Changing the speedo head on an A1R will just pull the same mileage from the MMDC as the previous speedo head. They are CANBUS gauges and only display what they are told to display. You can check the CAT computer to see if it's similar to the speedo readout (they absolutely track mileage - in fact I can change that value to anything I want) - but it's not uncommon for the MMDC's to get swapped out so 2400 could be wrong. Or it could be right. I have an MMDC around here somewhere with 35 miles on it. The air tank transducers in them fail and they get swapped out but otherwise usually work fine. I have opened them up and changed out the transducers.

The reality is that mileage really isn't actually verifiable and really isn't that important on these trucks. Condition is subject more to age and level of neglect than mileage in the case of FMTV's. 2400 miles on a 2008 indicates VERY low use. That means exceptional amounts of not being used which comes with it's own detrimental effects. Lots of issues with moisture, corrosion (especially electrical connections), sun damage, etc. Tires will be garbage if original - dangerous to drive across the country on 2008 rubber. I got lucky when I did it - got about 8,000 miles out of my 2008 tires (truck and tires had 2750 when I got it) and then lost a sidewall in spectacular fashion. That was 2021 so they were 2 years newer than they would be today.

Yeah that happened to me like last week! 2008 tire and I was only doing about 15 miles an hour. Luckily all the rest of my tires are less than 10 years old

 

[GCecchetto]

I’m reluctant to ask this here, but from what searching I’ve done, it seems this thread has the most info about running the 370hp tune on a C7. Earlier in this thread it was said the only difference in the C7’s delivered with the 370hp tune is the water cooled turbo. Talking with the guy I’m buying my truck from, he said his CAT tech told him the injectors are also different. Can anyone confirm if this is the case. The truck I’m buying is an M1078A1R, so originally delivered with a 275hp tune.

By the way, I’m in the airport on my way to Maryland to look at the truck

 

[GeneralDisorder]

I’m reluctant to ask this here, but from what searching I’ve done, it seems this thread has the most info about running the 370hp tune on a C7. Earlier in this thread it was said the only difference in the C7’s delivered with the 370hp tune is the water cooled turbo. Talking with the guy I’m buying my truck from, he said his CAT tech told him the injectors are also different. Can anyone confirm if this is the case. The truck I’m buying is an M1078A1R, so originally delivered with a 275hp tune.

By the way, I’m in the airport on my way to Maryland to look at the truck

They are not. He is incorrect. I have done extensive research into every engine part number that could possibly be different (cylinder head, pistons, camshaft, injectors, turbo, etc) and they all come back the same except for the turbocharger and deeper investigation confirmed it was the same Borg Warner S300 just with an oil/water CHRA housing instead of oil only.

 

[GCecchetto]

They are not. He is incorrect. I have done extensive research into every engine part number that could possibly be different (cylinder head, pistons, camshaft, injectors, turbo, etc) and they all come back the same except for the turbocharger and deeper investigation confirmed it was the same Borg Warner S300 just with an oil/water CHRA housing instead of oil only.

Cool, thank you!

 

[GCecchetto]

So, I committed to buying the truck yesterday so I’ve reached out to Mike to order the hubs. I am a little concerned about the tires for the trip home though. One of the tires is a 2017 date code, so not worried about it, but the other three appear to be the original tires with 2008 date codes. They look to be in good shape, but the 2017 tire was the spare, which had to be put on the truck when it was picked up due to the one tire being flat with a delaminated side wall. It was in the bed of the truck and wasn’t pretty looking. Don’t want that happening to me on the way home. The truck will have a new spare for the trip, but still concerned about three tires that are that old. They’re Goodyears and Berend told me he’s never had a problem with one of them coming apart on the road, but the one in the bed certainly appeared to have.
Overall condition of the truck isn’t worrying me much, but there is some weird stuff too. Like the rear drive shaft in the photo below. It looks like it lived its life submerged in salt water and has pretty significant pitting from the rust.

 

[TomTime]

Considering the good condition of the rest of the undercarriage of the truck, the shaft may have been a used replacement. If the shaft had been removed or was replaced I would check the shaft to be sure it is in operational condition. Check that the universal joints are good and that the shaft and joints were installed correctly.

 

[GCecchetto]

Considering the good condition of the rest of the undercarriage of the truck, the shaft may have been a used replacement. If the shaft had been removed or was replaced I would check the shaft to be sure it is in operational condition. Check that the universal joints are good and that the shaft and joints were installed correctly.

I was also wondering about that. There are other parts that are very rusty too and there is plenty of evidence of the truck being an east coast truck where chemicals are used on the roads, but the condition of the few really rusty parts like the rear driveshaft seems to indicate those parts not being original.

I’ll have to educate myself as to what is correct assembly of the U-joints and will talk to the seller about it as well since I’m certain he knows what is correct.

Can anyone point me to a good part# resource for these later model trucks?

 

[GeneralDisorder]

2008 tires are garbage. One of my 2008 Goodyears let go on the freeway last year. Sidewall failure. Don't attempt it. Get new tires before you drive it. The tire in your picture of the driveline looks like hell.

The driveline rust doesn't concern me more than the tires. Probably poorly prepped before it was painted. And the east coast did the rest.

No covers for the caging access holes on the brake actuators - ensure you still have caging bolts in case you need them and get new covers.

The OG u-joints are Meritor and say SINGAPORE on them. And the cap bolts are break-away bolts with Nord Lock washers.

 

[GCecchetto]

2008 tires are garbage. One of my 2008 Goodyears let go on the freeway last year. Sidewall failure. Don't attempt it. Get new tires before you drive it. The tire in your picture of the driveline looks like hell.

The driveline rust doesn't concern me more than the tires. Probably poorly prepped before it was painted. And the east coast did the rest.

No covers for the caging access holes on the brake actuators - ensure you still have caging bolts in case you need them and get new covers.

The OG u-joints are Meritor and say SINGAPORE on them. And the cap bolts are break-away bolts with Nord Lock washers.

Already confirmed the truck will come with caging bolts and new covers.

 

[Third From Texas]

So, I committed to buying the truck yesterday so I’ve reached out to Mike to order the hubs. I am a little concerned about the tires for the trip home though. One of the tires is a 2017 date code, so not worried about it, but the other three appear to be the original tires with 2008 date codes. They look to be in good shape, but the 2017 tire was the spare, which had to be put on the truck when it was picked up due to the one tire being flat with a delaminated side wall. It was in the bed of the truck and wasn’t pretty looking. Don’t want that happening to me on the way home. The truck will have a new spare for the trip, but still concerned about three tires that are that old. They’re Goodyears and Berend told me he’s never had a problem with one of them coming apart on the road, but the one in the bed certainly appeared to have.
Overall condition of the truck isn’t worrying me much, but there is some weird stuff too. Like the rear drive shaft in the photo below. It looks like it lived its life submerged in salt water and has pretty significant pitting from the rust. View attachment 904531View attachment 904533

Awesome stuff, but time for it's own thread I think

You might have surpassed the ECO Hubs topic here.

Just sayin'



And get one of these before you make a road trip. And a spare u-joint.

Because...reasons.

https://www.amazon.com/gp/product/B0787C31T1

There's a couple good threads on what tools you want to carry cross country with these trucks.

 

[Ronmar]

Yea if you are going to run any of them, I would put the 2017 spare on the front and put a new tire on the other front…

 

[GeneralDisorder]

Awesome stuff, but time for it's own thread I think

You might have surpassed the ECO Hubs topic here.

Just sayin'



And get one of these before you make a road trip. And a spare u-joint.

Because...reasons.

https://www.amazon.com/gp/product/B0787C31T1

There's a couple good threads on what tools you want to carry cross country with these trucks.

Yep. Have that same tool. Works GREAT. Just did all my u-joints with genuine Meritor R-279X's (also made in Singapore like the originals).

 

[GCecchetto]

Awesome stuff, but time for it's own thread I think

You might have surpassed the ECO Hubs topic here.

Just sayin'



And get one of these before you make a road trip. And a spare u-joint.

Because...reasons.

https://www.amazon.com/gp/product/B0787C31T1

There's a couple good threads on what tools you want to carry cross country with these trucks.

Yes agreed, I'm planning to start a thread specific to yet another newbie needing a bunch of advice and having loads of questions

 

[GCecchetto]

Yep. Have that same tool. Works GREAT. Just did all my u-joints with genuine Meritor R-279X's (also made in Singapore like the originals).

Got a link to the recommended place to purchase them?

 

[GeneralDisorder]

Got a link to the recommended place to purchase them?

They are all over ebay. Just search the NSN. 2520-00-388-4197

Here's a good one for a full set:

4x USGI M939 5-Ton Trucks Meritor Universal Joint 2520-00-388-4197 | eBay

THIS SALE IS FOR ALL 4 PIECES.

www.ebay.com

Looks like that auction doesn't include the bolts but you can clean and re-use. Just use a dab of blue locktite. Torque to 30 Ft/lbs.

Retail from the online parts dealers is way over $100 per. Uncle Sugar pays about $45 each

 

[GCecchetto]

They are all over ebay. Just search the NSN. 2520-00-388-4197

Here's a good one for a full set:

4x USGI M939 5-Ton Trucks Meritor Universal Joint 2520-00-388-4197 | eBay

THIS SALE IS FOR ALL 4 PIECES.

www.ebay.com

Looks like that auction doesn't include the bolts but you can clean and re-use. Just use a dab of blue locktite. Torque to 30 Ft/lbs.

Retail from the online parts dealers is way over $100 per. Uncle Sugar pays about $45 each

Thank You!

 

[Skyhawk13205]

I recently installed my ECO hubs.

Install,
he process was pretty straight forward, removed bevel gears, retorqued spindle nut, installed split collars, installed adapter plates, then installed the hubs. The part I spent a while was trimming the snap ring for the rear axle, I used a file and a vise to get it just right to plane it down to the right size. I found it hard to remove the trapped silicone. I used a small screw to extract the trapped silicone.Another part I found difficult was servicing the front hub. I took a 3/8 Vinyl tube cut a bevel then spun it into the servicing port. After install and servicing was done, I readjusted the engine ECM PPM to 31309. I adjusted my CTIS pressure to 70 psi HWY and over speed at 65mph.


Drive,
I went for a test drive, the acceleration was about the same, the noise was lower and the engine and driveline speeds were reduced. The truck was more slippery, it does not slow down when I let off the accelerator, I have the use the brake more than before. I was speed limited to about 60mph due to tyre vibration.

Observations,
The hubs were very well made, the fitment was almost perfect, the design was well thought out and implemented. It was well packaged and shipped fast Mike did a great job in building these.

Bevel Vs Eco
My my observations of the stock hubs and eco hubs is that the stock hubs are more resilient and resistant to vibration. The travel path of the torque is though both spline sets. The hub in my opinion was not engineered to take torque though the cap attach bolts. The stock hub gearing helps to slow the truck, the reliance on the brakes is more noticeable now.

Solutions/final thoughts
For braking, I used the exhaust brake, it seemed to help significantly. The hub even though it may not be engineered to deliver torque thought the bolts, it does not mean it is not able. The over engineering of this truck should be more than sufficient, the vibration I can see as a problem, I would like to upgrade the bolt to allow for a nord lock or have bolts that can be safety wired. I would also suggest to have an annual torque check of the hub bolts. Removing the trapped silicone and torquing the bolts dry and evenly is really important on this install. Another problem I see is when removing the tyre and wheel assembly is the half moon blocks can interfere with the rim. The weight of the rim dragging across the block may dislodge or damage those blocks and possibly cause leaks. I think a solution would be to have an alignment/thread protector on the 12oclock wheel stud to space the rim and prevent dragging on the hub adapter plate. The main reason for me to upgrade was to reduce the driveline RPM, there are many catastrophic failures on the 4x4 that are due to vibration. Any steps to reduce that RPM will reduce the chances of ending up broken. I would say the net benefit of cost, ease of installation, fuel saving, and driveline down-speeding of eco hubs outweighs the risks.

 

[Third From Texas]

(removed because not ECO Hub related)