Build The Mule: My OM617 swap and other improvements

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haha yeah sort of...... Now that my die hard Toyota is giving me trouble i had to break down and make an account.
 
Thanks! For years I thought this was a International Harvester forum. haha. "IH" So are you happy with the swap?
 
***Update***

I picked up a set of fine spline 4.56 thirds (1 is open, other is OEM limited slip) from @orangefj45 yesterday while passing through Stockton on my way back to San Diego. These should help me be able to stay in boost while using 5th gear (.73:1). Right now it just bogs down below 65mph/anything other than flat ground. Also, it should allow me to start in 2nd gear a bit better. The quick shift from 1-2 is getting old.

I started tearing the rear axle down tonight. I hope to have them in by this weekend. I'll report back.
 
I know exactly what you are going through. My jeep has 3.73's and could really use a re-gear. My overdrive is .75 and is completely useless unless i'm going down hill or over 75mph. Looking forward to hearing how it runs with the new gears. What size tires are you running by the way?
 
B613 said:
I know exactly what you are going through. My jeep has 3.73's and could really use a re-gear. My overdrive is .75 and is completely useless unless i'm going down hill or over 75mph. Looking forward to hearing how it runs with the new gears. What size tires are you running by the way?
Click to expand...

Yeah, this thing would be a dog with 3.73s since I'm running 33x10.50 BFG A/T's. Right now, I have to use 1st if I don't want to be a traffic hazard. My first gear is 6.34:1, so it's useless at about 5-7MPH.

I have not messed with injection timing, injectors, or the ALDA though and I don't really want to right now.
 
My jeep was pretty dead until I made a few simple but very noticeable adjustments. The alda mod is a must. You wont believe the difference! Clean out the little fitting and hose for the boost sensing line and grind off the tamper proof cap and give it a few turns... You really cant hurt anything so play around with it. Find a good balance of power and smoke. Makes the engine much more responsive pre-boost. I especially noticed taking off from a stop in second gear. My t-18 has a 6.32 1st so it was slow like yours. The other adjustment I made was to the waste gate. I was only making about 6psi max.... I adjusted the spring a little now I can hit 15psi pulling hard in 3rd or 4th gear around 2500rpm with a max EGT of 1100. It runs great. I haven't done anything else to it... I would also recommend doing a "diesel purge" if you haven't already done it... It made it smoother starts easier and got rid of the black smoke at idle. My jeep moves along really well in anything but overdrive....and im running 3.73's with 32" tires. So your cruiser should be awesome with your new gears and 33's.
 
Holy crap, 6.34 first gear! That's freaking low. I ran an H41 (4.95 first gear) with 4.10 gears and 35's on my FJ55 and it seemed to be a good balance when taking off from a stop. My top end didn't suffer with that combo.
 
looking forward to hearing how the 4:56 run. I have them in my 62 but with my new engine they're too low so I need to go back to 4:11. I want to use the 4:56 in my 40 then as I'm running the same engine/tranny as you are. still waiting on my adapter kit though. it's really driving me nuts!!
 
Well here's an update on the 4.56s:

F'ing money t*ts!!!

Overall the swap was really straightforward except I didn't listen to @orangefj45 when he told me the limited slip had to go in the front. Well, I f'd that away and got to remove a crapload of "the right stuff" (silicone sealant) for transgressions in addition to undoing everything I'd already done.

Drilling the pinion flanges was a motherb*tch. That metal is tougher than woodpecker lips. Drill bit size is 7/16" for an ~11mm hole.

Bottom line:

If you're going to run an NV4500 and 33" or bigger tires, you better run 4.56s, at least. I live in San Diego and it's pretty hilly in north county and I used to be a traffic hazard in the far right lane pulling hills at about 45mph. Well, not anymore. 2nd gear starts are now the norm, my foot is not "in it" all the time, and I can cruise down the highway in 5th gear without bogging.

Overall the Mule is MUCH MORE enjoyable to drive now. I can't believe I waited this long to make this happen.

I'll try to get actual numbers when I can, but at a glance I saw about 70mph, 2400ish rpm, 10-11PSI, 1100EGT, 5th gear.
 
So, I decided to do a garage driveshaft lengthening of my front driveshaft... It was super straight when I tacked it together with almost zero radial runout. Well, for anybody doing this type of DIY stuff, be aware of your heat when you glue it all together. I ended up with a significant (~1.5cm--sorry my dial indicator is .001cm graduated) amount of runout. So, I decided to try my hand of "flame straightening." I was amazed at how much you can straighten a tube by this method. It's a subjective method, but you just keep doing a little bit at a time. The key part is heating then quenching. Pretty cool I think! Anyways, I know have the 4.56 LSD in the front and 4.56 in the back from @orangefj45. Gearing is sweet!
 
Here are some pics

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Update***

I had to flame straighten my front drive shaft as it had some radial runout, but it's true now and runs without any vibes as far as I can tell...

In other news, I'm thinking about installing some aftermarket bucket seats. I don't really want to change the stock look of the interior, but with all my back problems it may be the only way I can stay in this thing without getting too banged up. After an few "flare ups" of my back I usually want to sell the Mule. Then I come back like a battered wife...

Any suggestions on seats and seat frames out there?
 
You might want to look into Monte Carlo seats, pretty close in style and way more comfortable.

John
 
Thanks for the replies. I'm on the prowl for some BMW M3 seats. Heated would be a BIG plus, since I'm having some serious back problems (actually leaving the military this year due to it)...

I guess I need to learn how to bend pipe to make a seat cradle.
 
I have to admit, I'm a bit bummed about how hard the Mule is on my back. I keep having errant thoughts of putting it up for sale to get something a little easier riding. Am I crazy? Maybe I should go SOA with my original springs. Does that soften the ride considerably?

Maybe I'm just being rash....
 
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