"DIY" hd mcnamara gear

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back to the regularly scheduled program.......

well, got to the shop today and the gear was still warm to the touch, almost body-temp. pretty amazing how well a welding blanket insulates heat. after a quick dunk in the solvent tank, some scrubbing and a quick buffing on the wire wheel, the long splined gear was ready for install. got the t-case done today. pretty snug fit, it's definetly going to require a puller to get the gear back off when the need arises. i figured i'd rather have a tight fit than start tinkering with a file and possibly create some slop.

either way, it worked out. if anybody wants to borrow the "jig", they're more than welcome to hit me up.

hth

georg @ valley hybrids
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orangefj45 said:
that's a loaded question. the splines usually start showing significant wear at 150k miles and more. i guess if you plan on having the cruiser for a looooong time, then it's a good investment to install either a genuine or diy long spline gear setup. if you're gonna drive it rarely or plan on selling in a couple of years, then it might not be a great investment. ultimatley, installing a McNamara gear behind a new h55f trans would be the way to go. decisions, decisions................
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Yeah it's a DD, for sure. My goal was to make the Duster a DD, but until I have a stereo in it, it's just my rolling restoration to be driven during the summer :D
Since I have plenty of time, I'll look at building up my welding skills and then do up my own maybe next year. Be great to not spend $400 and wait for it to be shipped from Australia. Maybe instead of asking to borrow your jig, I'll have to make a road trip out to your shop so you can help me do up a gear and we can discuss Cruiser stuff over a couple beers :D

Those welds look clean as hell. I don't forsee that ever coming apart...
 
orangefj45 said:
well, got to the shop today and the gear was still warm to the touch, almost body-temp. pretty amazing how well a welding blanket insulates heat. after a quick dunk in the solvent tank, some scrubbing and a quick buffing on the wire wheel, the long splined gear was ready for install. got the t-case done today. pretty snug fit, it's definetly going to require a puller to get the gear back off when the need arises. i figured i'd rather have a tight fit than start tinkering with a file and possibly create some slop.

either way, it worked out. if anybody wants to borrow the "jig", they're more than welcome to hit me up.

hth

georg @ valley hybrids
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My gear was still snug even after filing. I did have to use a puller when I took the case apart 3 years later. It fit the splines on the Advance Adapters NV4500 adapter a bit tighter than the original splines. Nice job on the welding!
 
Georg,
I have a splitcase behind a 700r4 on my Cummins setup and was wondering if you had ever seen anyone needing a McNamara gear on a setup like that? It's using the Advance Adapters 700r4 to Splitcase adapter. I'm getting a loud clunk sometimes in reverse and have checked the drive shaft/u-joints/rear diff and all look good.
 
Probably cheaper to buy a new spud shaft from AA. I think they are around $175.

Dyno
 
69rambler said:
How much is a McNamara gear? How many people actually need one of these a year these days?
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Round about $400-$450 I think. West Coast Cruisers imports alot of "exotic" Cruiser parts and sells a long spline input (not sure if it's a McNamara) gear for $458. Quality-wise I wouldn't hesitate to spend the money for a McNamara, but if he could be talked into doing one up, I'd rather get a homebrew gear from Georg. That way you're still supporting a stateside Cruiser guru who's a huge contributor to the Land Cruiser community. My tcase from him only has about 5K or so miles on it so it's got a long time until a rebuild is necessary, but a fully splined gear from him or a sourced McNamara (IMO) is mandatory for a tcase rebuild.

To touch on your 700R4/Cummins issue, I'd be willing to bet the extra torque from the Cummins has caused a good deal of spline wear on both the spud shaft and the input gear. In that case, for the sake of longevity I'd at least get a fully spline input gear, and depending on how much wear you can see on the spud shaft, a new one of those as well. Best to start of clean with brand new splines the whole length since that'll buy you the most wear resistance over time.
 
Thanks for the info. I've been asked to machine full spline 60/62 gears before and the price for a handful can't compete with $450.

Personally, I would be very hesitant to sell a welded up gear like that. There's too much work to do it and sell it cheap, too much that can go wrong to stand behind it. Gears like that are not made from alloys that are considered weldable, not to say you can't do it, but you can't realistically bank on it working when you use materials in a way they aren't designed.

If you had 20+ that wanted to buy a gear I think the price would get pretty good and a bulletproof new part could be made from better than OE US materials right here in the US.

I somewhat doubt there's enough demand to make and sell a batch of twenty and $450 isn't too hard to swallow if/when you absolutely do need it.
 
Friend of mine had the transfercase input gear, spacer and PTO gears welded together by a local shop. Instead of bringing just a section of transmission output he brought a whole spare A440. The welder prepped and welded the gears, then slid them off the spare transmission and we installed into the transmission in the truck, no problems.

I recommend finding a local welder you trust and having one made.
 
Who has Georg's jig? Please PM me, I will return it to Georg when I am done.
 
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