Ahhhh ok here's another... I know this has become a crap load of tech so I hope you're ready for some more-
Original Post:
http://www.pirate4x4.com/forum/showthread.php?t=165571Date: 08-06-2003
Edit: On the Marlin crawler website their new adapter have bigger bearing and they make it seem like the bearings in the advance adapter kit suck. Is that true...are they inadequate?
This is likely a matter of opinion and what you use your truck for. Our old MC05 Adapter plates used a main bearing that is weaker than stock. It was originally used out of convinence. A/A uses this same narrow bearing in most of their other product lines (eg. 350 adapter, 700R4 adapter, T18 adapter, NP435 adapter, etc) only as an idler bearing to support the main shaft coupler of those adapters. It was never intended nor is it strong enough to support the low range load requirements of a Toyota transfercase. Marlin had originally designed the MC05 to
have the double roller bearing in July of 1998, however A/A declined to use it and rather opted to use their common bearing that was much cheaper and hundreds in stock. Marlin tried for more then 1 1/2 years to get the bearing upgraded to the double roller that we use today. It is true that the MC05 is inadequate for a reliable and long-term application. However, it does function as it's supposed to and will provide your vehicle with a lower Crawl ratio.
Quote from TNToy:
Furthermore, the small bearing design that AA currently sells is what Marlin sold until about two years back, when he stopped selling it and started making the bigger-bearing adapters.
Yes, this is the one. But two things, For some reason, people on this board continue to believe that we just stopped selling the MC05 yesterday and that we sold so many of them.
We stopped selling the narrow MC05 crawler almost 4 years ago. Also Marlin had tried to convince A/A for more then a year and a half before then to upgrade to the double roller and they
finally did it but at the cost of retailing the MC05. This is similar to why we discontinued the Marfields, because the manufacture was unwilling to improve the design. At about ~ MC05 #0440-#0450 A/A finally made the switch. Since then more then #1500 Double Roller MC07 Adapters have been sold. And we had A/A starting to make design changes by around by #0300.
So if you put it into perspective, the Double Roller MC07 has out-sold the Narrow MC05 early crawler 6 to 1 (1800/300 = 6). Clearly we did not sell nearly as many of the narrow MC05 crawlers as compared to the Double Roller MC07 and we're so glad to see that we distributed a weaker then stock setup for only a very short period of time.
Quote from TNToy:
Yes, Marlin's bearings are better... however, I know people who have been running the "AA" setup for over 5 years without trouble or excessive wear.
You know, people talk all the time how
I've been running my MC05 for like 10 years this and
8 years that and
I don't have any wear or problems But you know what the reality is? A majority of our MC05 customers who have returned to upgrade to an ultimate, have excessive and often severe wear to the MC05 coupler. When we open up the crawler to inspect how the coupler is, we see noticable wear at the place where the narrow bearing sits and the splines are all but gone. Because the bearing is so narrow, the couple waddles - or teeters - from side to side. This is because the narrow bearing does not have enough support to prevent the coupler from waddling. And once the coupler waddles more and more, the splines encounter very bad premature wear and this is why alot of the MC05 couplers strip out. You'll notice a worn out coupler right away from the brown-orange powder and the fine dust that is developed from the splines stripping each other out (see picture below).
This is a MC05 coupler that we have saved untouched from a customer who drove his truck in for an ultimate upgrade (installing a 4.70:1 gear set). Untouched. All that crap was in his coupler as he drove to our shop. It ran fine, crawled fine, shifted fine, but it was only a matter of time until it stripped out. Those teeth are so worn out you dont even want to know (look close at the peeks of the teeth inside the coulper, they are narrow from being ground away) . And this is not a one-of-a-time-occasion, this is how all alot of the MC05s that we've opened up look like. We send these couplers back to A/A for warrentee every time. This is from many many miles of the coupler waddling and wearing away at the splines until its to late. Never ever have we seen a MC07, MC08, or MC09 coupler look like this. Even the early MC07s from 3-4 years ago. No more orange crap. That is all caused from many hours of splines grinding away at each other. The Doubler Roller bearing has more then enough support and exceeds the low range torque requirements to prevent the waddling, problem solved. Its 5/8" wider and has two sets of rollers amounting in 32 total bearings as compared to 9 (MC05 narrow bearing). Obviously Marlin was wise when he improved the Crawler design.
TNToy, sure the MC05 Crawler may be trouble free, but what's really going to look bad is when they reach their life expectancy and all of a sudden we start hearing about MC05 bearings going
out. Then you'll know why things are upgraded when a machinist feels it's to weak. And honestly I doubt that you know of anyone who's without excessive wear. Have they ever opened up their
case and inspected it? How can one tell the difference between gear backlash and coupler slop until they open it up and look first hand. I'm sure their unit is working fine and shifting well, I'm not arguing this, its just that you'll not going to know about your worn out coupler until its too late. We have given away alot of input gears for free to replace stripped ones, and we've opened up more then just a couple. Also, we have had MC05 crawlers that wont even seperate! The splines on the input get gets caught on the end of the worn out MC05 coupler teeth. We have had to hold the input on the crawl box, and turn the rear t/case backwards to unhook and release the input gear.
They weren't broken, please don't confuse this, of course its not stripped yet, but its on its way, theres no doubt about it.
So what am I saying? Is the MC05 going to fail? Yes. Is it weaker then stock? Yes. Is it a poor design? Most definitely. But the ultimate question is "when?" Sure I've seen MC05s run for 4 years too but just don't go around telling people that their is no difference with the MC05 vs. the MC07! That is a lie in its purest form. I understand that the MC05 and the MC07 are both dual case crawlers, but that's like saying your Ford Tempo can get you from point A to point B just like a Mercedes S600 but I promise you that one is not as good as the other and that one will break down many times and many years before the other.
This is a stripped out MC05 coupler. Ouch.
And the funny thing is that when our customer is here looking at his MC05 Crawler that we sold him 4 or 5 years ago, and he sees how worn out it is, we have never had anyone want to continue to run it. They are amazed at the wear and they can't believe how it was still working! Once they see that they immediately upgrade to the Double Roller MC07 without even blinking an eye at the price difference. Now thats a cool product.
I looked on advance adapters website and it says the adapter only works with 80-83 t-cases, are those years hard to find?
That is half correct. Their adapter works with 1980-1983-ALL and 1985-1988-EFI(non-turbo) transfercases. If your looking for similar tech questions regarding how the Dualcase system works and what's involved with its installation, feel free to browse our forum at
http://board.marlincrawler.comAre the kits pretty complete or will I need to buy some other stuff?
Their kits will require a speedometer cable extension (all 1984+ applications), you'll have to press out a cage roller bearing from your donor t/case, and your also have to retrieve two dowel pins from the donor t/case. Also no shift light plug or transmission output seal is supplied.
Quote from toy_grove:
Don't forget that your stock c-member will need to be changed.
This is optional and is not required. The stock crossmember can be used in the stock location just fine. On high lift applications, the front of the crossmember will need to be clearanced for the CV Joint.
Quote from 85runnerAZ:
So you're saying Marlin is a better way to go even though it is more $$$...
It is better and it costs more because it uses stronger maximum heavy duty parts, and we pre assemble the plate by pressing in the double roller bearing, installing the 3-bolts, we supply and press in the cage roller bearing and lube it, we install the two dowel pins, we supply a shift light plug with gasket, and a new genuine Toyota Transmission output seal. This is how Marlin shows that he goes above and beyond what's needed - He even supplies a new Toyota Transmission output seal. How cool of a guy is that? Also, we include our new Marlin Crawler Turtle Shift Knob for free.
But 85runnerAZ, I could sit here all day telling you why this is better, and that, and this, and that, but it comes down to what you need for your truck and what you plan to use it for. If your truck is not a daily driver and maybe you even plan on selling it some time, then all of this information that I have been telling you about may not apply to you and then its purely a matter of cost. But I really wish that people would just use the facts that have been presented on this message board in the past so that we can all think for our own selves and order what we feel is right for what ever the needs are.
Quote from cruzer75:
What is the size (ODxIDxwidth) or the number and manufacturer of the [MC05] bearing...
cruzer75, this is not the problem with the MC05 crawlers. Even if you are able to find a stronger bearing that has those same dimensions, its still to narrow to prevent the coupler from waddling. The bearing is just to narrow and is under-rated for the application, period.
Regards,
BigMike
So that settles the MC05 vs. MC07 question and problems with weak bearing designs.Regards,
BigMike
