Topic: Understanding the Success of the Marlin Crawler Dual Case

[BigMike]

This is an article that should have been written in 1999.

Due to what I consider to be misleading and inaccurate information, I have written this article to address the differences with the old Marlin Crawler (1995 MC05) and the new Marlin Crawler (1999 MC07), and to explain why the design changes are so important and have been proven EXTREMELY successful.

This article was written by me and is currently a work-in-progress. A "Last Updated" date is provided at the bottom for reference.

The article covers the following:
I. History and Development of the Double-Row Bearing Toyota Dual Case Adapter
II. Double Row Maximum Capacity 32-Ball Bearing
III. Redesigned Coupler with a New Thrust Washer Detent Ball
IV. Increased Oiling Capacity
V. New Bearing Retention System

However, at this time, only sections I. and II. are completed.

My original goal was to fully complete the article, but due to overwhelming phone calls with questions regarding our MC07 Crawler in the recent weeks, I have elected to release the article in a work-in-progress state.

I expect to have the article fully completed in the upcoming weeks. I will announce each update that is made here.

Please click below to read the article:
Understanding the Success of the Marlin Crawler

I hope this article clearly defines why the Marlin Crawler has been so successfull, and resolves any confusing information you may have regarding the Toyota Dual Case Crawler.

Regards,
BigMike

[AaronB]

Well now I know I have a MC07. I wasn't sure what I had! Awesome rite up.

[Duffil]

wow...didn't realize it was that much of an issue.  Good info though, Mike.

[BigMike [OP]]

wow...didn't realize it was that much of an issue.  Good info though, Mike.

It is a HUGE ISSUE that should have been addressed LONG AGO.
There are more very important changes that I will be covering soon in the article. These changes are done not only to just the MC07, but the entire family of Marlin Crawlers since then.

The Marlin Crawler Double Row Maximum Bearing Line of Dual Case Adapters all have the same important key reliability changes. These include, but not limited to:
MC07
MC07-R10
MC08
MC08-R10
MC09
MC09-R10
MC10-R10

The 3,200 Units mentioned in the article are ONLY referring to the MC07. If you were to include all of the 5209W Crawlers produced by Marlin Crawler, then it would be well in excess of 4,000. These other Crawlers have NEVER FAILED TO THIS DATE. Including the 3.0 and 3.4l V6 Setups. We have never had a single coupler failure. Never.

Imagine using a dual case adapter with the 6209N bearing behind a Supercharged 3.4l Doublecab Tacoma. It is so absurd I can't even think about it. And yet we have countless MC09 and MC09-R10s doing just that with ZERO failures.

<a href="http://www.youtube.com/v/dZShaRavFEg" target="_blank" rel="noopener noreferrer" class="bbc_link bbc_flash_disabled new_win">http://www.youtube.com/v/dZShaRavFEg</a>

Our track record is proof to our reliability.

BigMike

[boggerunner]

i know a guy here in town runnin a MC01, how many of those were made? and how many are still around?

[BigMike [OP]]

i know a guy here in town runnin a MC01, how many of those were made? and how many are still around?

Wow! That is incredible! The MC01 was so long that is used two separate single-row bearings to support its mainshaft (sound familiar?).

I believe about 15-MC01s were produced and about 20-ish-MC03s. Since the MC05 and MC07 are of a different design, the serial number was reset to #001 with the first MC05.

[boggerunner]

were there any problems with the mc01 besides the length?  i bet that thing has some miles on it, and its in a 79 with a 20r and an 84 cab and bed on it

[BigMike [OP]]

were there any problems with the mc01 besides the length?  i bet that thing has some miles on it, and its in a 79 with a 20r and an 84 cab and bed on it

Wow! That is incredible! The MC01 was so long that is used two separate single-row bearings to support its mainshaft (sound familiar?).

Ok, I spoke to Marlin about this before he left for work.

The MC01 has two mainshafts. Or maybe better worded, 1 Mainshaft and 1 Output shaft. What Marlin did was take a factory output shaft, which is 11.25" long, and cut it down to 5.25". He then placed a coupler behind the shortened factory output shaft that connect the rear t/case input gear with the splines on the factory output shaft that drive the front wheel drive.

Let me explain it again. The MC01 has two shafts.
The first shaft is the mainshaft. The mainshaft is a factory t/case output shaft that is shortened. This shaft has the 1-6209N bearing and connects the reduction gears to the second shaft.
The second shaft is the output shaft. The output shaft uses an even smaller bearing, and connects the mainshaft with the 2nd transfercase.

The problem with the MC01, besides its length, is that the output shaft connects to the shortened t/case mainshaft using the front output splines that are Only 9/16" long and have a small diameter.

Out of the dozen-ish that were sold, nearly 3/4 of them failed. Those 9/16" long splines kept stripping out on the output shaft. They are too short and too small OD.

When I told Marlin that a MC01 is still in use he was very amazed. It's like his little baby that he set out into the world maybe 10 years ago and its still working. That is sooo cool.

Your friend has a relic in his truck. If he ever sells his rig or something, he should keep the MC01 and put it in a trophy case!

[BigMike [OP]]

Ok, here is an illustration to help visualize the MC01.

Also, I think it was only offered in a 21-spline setup. Like other Crawlers that use a modified t/case mainshaft, it can not be used with a 23-spline drivetrain.

[boggerunner]

nice, thanks for all the info, next time i see him, im gonna make an offer on it, or at least get some pics

[BigMike [OP]]

I've had a couple of requests about the "I've Got More Balls Than You" image in my signature, so I just figured I would share the code with who ever would like to use it on our forum or anywhere else.

To get this:


You'll need to put this into your Signature in your Profile:

Code: [Select]

[url=http://www.marlincrawler.com/docs/mc07/index.htm]
[img]http://www.marlincrawler.com/docs/mc07/comp_moreballsthanyou_250t.gif[/img]
[/url]
Or if you wish to place it on a website, then use the standard HTML code instead of the Forum code, like this:

Code: [Select]

<a href="http://www.marlincrawler.com/docs/mc07/index.htm">
<img src="http://www.marlincrawler.com/docs/mc07/comp_moreballsthanyou_250t.gif" border="0">
</a>

[MiniSimp]

Ok, I want a full write up on the MC08-R10 now!

Good job Mike!

[Rocksurfer]

You guys need to make that a sticker with the round Marlincrawler sticker behind it, everyone will want one.

[BigMike [OP]]

We actually have a couple of good sticker ideas that some of us have already made and are using them on our rigs.

[Hottrod81]

Make them before you say anything about them.  The ideas might get stolen.

[MiniSimp]

We actually have a couple of good sticker ideas that some of us have already made and are using them on our rigs.

[KYOTA]

We actually have a couple of good sticker ideas that some of us have already made and are using them on our rigs.

hook a brutha up  8)

[MT4Runner]

The Marlin Crawler Double Row Maximum Bearing Line of Dual Case Adapters all have the same important key reliability changes. These include, but not limited to:
MC07
MC07-R10
...
BigMike

Foreshadowing?  I love it!!!

[BigMike [OP]]

I have done more testing on a Single Row (6209) bearing vs. our Double Row (5209) Bearing, and the results of which blew me away. I was not expecting this much from this.

I have not updated the "Understand the Success....." thread with this info yet. I will do that as soon as I get some more free time.

This all started when 4RnrRick made the following, most excellent suggestion:

If you have ANY DOUBT that a double roll bearing is no different than a single, then please see my video comparing a 6209N bearing vs. a Marlin Crawler Double Row bearing:
http://youtube.com/watch?v=dZShaRavFEg
....
Regards,
BigMike

Nice video!
Have you thought about using a Dial indicator say 1" away from the surace to compare the movement.... obviously the single has the ablility to move around a lot more....

I don't know why I never thought about doing this when I wrote the "Understanding the Success...." article. I got time to investigate it last night, and the results were more than I had expected!

I'm sure many here have already seen my video regarding the 6209 Single Row bearing vs. the 5209 Double Row bearing on YouTube (see above link), so here is a follow-up on the issue.

What I did was I took one MC05 Crawler with a new 6209 Single Row Bearing and one MC07-R10 with a new 5209 Double Row bearing into a vice, and inserted a coupler with its c-clip so that the coupler is positioned in the same location as it is when in service. I took my measurements from the end of the coupler, near the location where the Low Speed Gear applies its axial loads to the coupler.

Here are the results from the MC05 Single Row Bearing Crawler:
Maximum Deflection: 0.025"



Here are the results from the MC07-R10 Double Row Bearing Crawler:
Maximum Deflection: 0.003"



And here is a video I prepared for this (Shockwave required to watch):
Click here if the flash player does not embed correctly
<a href="http://www.marlincrawler.com/docs/mc07/6209vs5209.swf" target="_blank" rel="noopener noreferrer" class="bbc_link bbc_flash_disabled new_win">http://www.marlincrawler.com/docs/mc07/6209vs5209.swf</a>

I highly recommend watching this video. Very surprising results. I had expected maybe 0.015" from our Double Row bearing, but only 0.003" is amazing. Even when I was beating on it, it would only peak to about 0.004".

This is why I believe that the Dual Case Kits from Marlin Crawler Inc is the best in the world, and I wouldn't want anything less in my truck.

BigMike

[MiniSimp]

Cool Vid, but the narrator has to go!
Could I get the audio clip of that guy going "Yeah...That's what I want...Right there!"

Good vid though Mike!

[46&2]

Good stuff. Thanks for all the information....though I already knew your kits are the best in the world.... 

[BigMike [OP]]

This new information has been added to the main article now...

http://www.marlincrawler.com/docs/mc07/index.htm


Also threw the video up on YouTube:

http://www.youtube.com/watch?v=esUqoQ_ChTA&v3

[Dr.Maxwe001]

sweet now if I can just get the other code for the falling balls I'd be set   any luck as to where to get it

[GNasty 82]

BUMP.....

Mike,
 Is this ever going to get updated?  I sure could have used the part about the thrust washer the other day when I was arguing with a friend.

 

[BigMike [OP]]

Not only do I need to finish that article, but it also needs to be re-themed and adapted to the new website layout/design. It also needs to be updated to include the new XtremeDuty dual case which totally blows away all the older designs too.

For now, as for the thrust washer, I wrote a short feature for that on the Exploring the New Marlin Crawler MC07 XD Technology page, use this link to jump to the Thrust Washer Lock section: Thrust Washer Lock System

[Rocksurfer]

Just goes to show that this is a company that is always on the move, even if it is very slow movement.... isn't it funny that moving slower than your competition is a good thing?

[GNasty 82]

By that logic, this will be the most awesome article ever, because it will crawl over every detail!
 

[Dr.Maxwe001]

 

Posted on: Today at 07:40:27 AMPosted by: GNasty 82  By that logic, this will be the most awesome article ever, because it will crawl over every detail!  
 

[BigMike [OP]]

[kneedownnate]

isn't it funny that moving slower than your competition is a good thing?

You may have just hit on a new slogan!  Marlin Crawler Inc., moving slower than the competition!