M939 Frame Extensions

I have a couple of questions on frame extensions. I'm going to add some to my M923A0 but have not seen any in person. This isn't for a winch installation...yet. I'm working on a bumper project and need room for the hood to open.

Is the extension in the picture below the correct extension? The NSN I was given matches the NSN from the TM, but I wanted to make sure before having them shipped.



Are the extensions side specific or are both sides the same? The TM only lists one NSN for the extension so I assume they are the same, right?

I need some pictures of the connector plates, from extension to frame rail, and how they attach. I will be making my own, unless someone has a cheap source for them. The extensions just happen to be NOS but used connector plates are fine. I'm getting them for cheap so if I can't find the connector plates for a decent price, I'll just make my own. I know the connector plates are side specific because the TM lists two different NSNs. Pictures of custom connector plates would also be appreciated.

Be careful, you can only use 939 extensions and inner pieces, 39 and 809 items WILL NOT work.

73m819 said:

Be careful, you can only use 939 extensions and inner pieces, 39 and 809 items WILL NOT work.

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Thanks Ron. He gave me NSN 2510-01-082-2515 and P/N 12255926 for the one pictured, which matches the TM for my truck. Your statement is why I want to check that the one in the picture matches the NSN. I just have nothing to compare to for a definitive answer.

The picture below is from the TM and it appears the bolt pattern is different, hence my question.

They do look different. And TMS are normally very accurate on there drawings.

Thanks for posting this thread as I was about to ask the same questions regarding extensions because I want to extend the bumper now and add a winch down the road.

Now I've just got to find a source for the extensions and connector plates at a reasonable price. The connector plates seem to be harder to find.

I remeber seeing this drawing a while ago in the manual and thought that it didn't match with the bolt pattern either, but I did not make mention of it on here because I didn't have a truck yet to put them on.
Hopefully someone else can chime in on this issue.

Except for the hole to nowhere looks like mine...

I have a set of extensions and connectors off a truck I'll get pictures of if you can wait a week for me to get back to Georgia. The extensions are still bolted to a winch, but I should be able to get some decent pictures of the parts that are harder to see on a truck.

rhurey said:

View attachment 539736

Except for the hole to nowhere looks like mine...

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After looking at the picture I'm going to give them a try. The extra hole is odd but the rest look to be correct. If they turn out to be wrong I won't be out much. With custom connectors I ought to be able to make something work either way.

Do you know if they are side specific?

Baradium said:

I have a set of extensions and connectors off a truck I'll get pictures of if you can wait a week for me to get back to Georgia. The extensions are still bolted to a winch, but I should be able to get some decent pictures of the parts that are harder to see on a truck.

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That would be great. I've looked through a lot of pictures and video but haven't found any good direct shots. The main thing was determining if they were correct so I can get them heading this way.

R Racing said:

They do look different. And TMS are normally very accurate on there drawings.

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This has also been my experience. Maybe this is an exception?

Oldworldtenacity said:

Thanks for posting this thread as I was about to ask the same questions regarding extensions because I want to extend the bumper now and add a winch down the road.

Now I've just got to find a source for the extensions and connector plates at a reasonable price. The connector plates seem to be harder to find.

I remeber seeing this drawing a while ago in the manual and thought that it didn't match with the bolt pattern either, but I did not make mention of it on here because I didn't have a truck yet to put them on.
Hopefully someone else can chime in on this issue.

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Let me get mine ordered tomorrow and I'll give you my source for the extensions if you'd like.

Swamp Donkey said:

Do you know if they are side specific?

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Both mine are the same. The "extra" hole is on the top on the other side and goes through.

Swamp Donkey said:

This has also been my experience. Maybe this is an exception?



Let me get mine ordered tomorrow and I'll give you my source for the extensions if you'd like.

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Hey, yes I would appreciate that and thanks.

the inner extensions appear to be the same. The exterior pieces look like they are right and left but only one hole difference maybe 2 that looks like it could be easily drilled.

Tried to upload 3 other pictures but it failed.

Send me email via pm if you need more.

juanprado said:

the inner extensions appear to be the same. The exterior pieces look like they are right and left but only one hole difference maybe 2 that looks like it could be easily drilled.

Tried to upload 3 other pictures but it failed.

Send me email via pm if you need more.

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you want to sell those ?? lol

R Racing said:

you want to sell those ?? lol

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No, thanks as I am adding a winch to mine and hopefully will be mounting it in 2 weeks with goldneagle's help as I just finished the wet kit. I removed those off a scrap wrecker by hand in July with no shade. Talk about brutal work

If I can get another set from a scapper, I will let you know.

juanprado said:

No, thanks as I am adding a winch to mine and hopefully will be mounting it in 2 weeks with goldneagle's help as I just finished the wet kit. I removed those off a scrap wrecker by hand in July with no shade. Talk about brutal work

If I can get another set from a scarpper, I will let you know.

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Thank you !!

juanprado said:

the inner extensions appear to be the same. The exterior pieces look like they are right and left but only one hole difference maybe 2 that looks like it could be easily drilled.

Tried to upload 3 other pictures but it failed.

Send me email via pm if you need more.

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Oh that's perfect. A shot like that is exactly what I need. I didn't realize the inner rails were so long.

Well, they made it. I've got a local fab shop that's going to press brake some inner rails for me. They'll also punch the holes. This will be the cheapest route for me and I can customize them a bit.

Juanprado, would you mind getting me three measurements off your inner rails? The three critical measurements I need are the actual full length and also the height and width of the notches in the corners. It would be much appreciated since everything else is going to be measured on the truck.

It'll be a couple of weeks before I can get them made but I'll post the progress here.

Oldworldtenacity, I'll PM you later this evening with the vendor if you'd like.

Swamp Donkey said:

Well, they made it. I've got a local fab shop that's going to press brake some inner rails for me. They'll also punch the holes. This will be the cheapest route for me and I can customize them a bit.

Juanprado, would you mind getting me three measurements off your inner rails? The three critical measurements I need are the actual full length and also the height and width of the notches in the corners. It would be much appreciated since everything else is going to be measured on the truck.

It'll be a couple of weeks before I can get them made but I'll post the progress here.

Oldworldtenacity, I'll PM you later this evening with the vendor if you'd like.

View attachment 540791

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I sure can. I need some time but will post up for you. We have this minor party here now that occupy us for 2 weeks or so

juanprado said:

I sure can. I need some time but will post up for you. We have this minor party here now that occupy us for 2 weeks or so

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It's going to take me a minute to make time to get up there so that'll be fine. Thanks!

Swamp Donkey said:

Well, they made it. I've got a local fab shop that's going to press brake some inner rails for me.

Oldworldtenacity, I'll PM you later this evening with the vendor if you'd like.

View attachment 540791

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Yep, please send me whatever you have. I want to put these extensions on as well and it seems to be a chore to find them for the M900 series...especially with the connector rails.

Also, I would be curious to know how much the fab shop is going to charge you to make the connector rails for the extensions.