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What did you do with your GMT400 today...or yesterday....

I can to the chalk test on them, but with them at their max rated PSI already (44) I'm not sure I can add any more if they need it. I'm sure the front tires are riding on the full tread with them near their weight capacity. unless I can increase them any. they are a 5 ply tread with a 2 ply sidewall from what I read on the side of the tires.
 
Blown turn signal fuse issue popped up again. BLUF, front left LED signal (12+ years old) was at issue. Incandescent bulbs back in.
Fuel Gauge locked on Full issue solved with a fill up and bumpy road. Guess the Metrum FSR floating measurement element got stuck at the top.
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Simple solutions are the best.
Now to rest my back after all of my son’s moving “help” failed to show up yesterday.
 
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Welp…. Houston I may have a problem…. I scored me a front bumper today and while I was installing the center brackets I discovered this oil leak!!

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That sucks. Had that issue last fall. Couldn’t find a direct replacement. Contact Leroy once you confirm fitting sizes (1/2” or 5/16”) and, if you’ve got the correct sized fittings, order just the cooler from him.
 
It looks like a factory cooler but it has Leroy's hoses so I'm not sure. I have another cooler but the fittings are some sort of orb o-ring type. not sure if I can get adapters for it.

The fittings in this one look to be 1/2" pipe to #8 jic or an fittings
 
I just did my cooler, one of my lines blew a hole. Made a nice mess all over my driveway.
I did not replace the cooler. But I did replace everything else.
My fittings were one size smaller including the hose.
I kept my old cooler, plan on doing the fan one under the cab.
 
I Got the bumper installed finally. had to do some slight tweaking with the floor jack to get it all lined up. it's not perfect but it's much better than it was without any bumper. Oh yeah and I forgot to post a pic of the newly installed stereo.

I also had my helper out there with me :D

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On the fitting for the OE cooler, I did manage to find that it's a special fitting. 18mmx1.5 male o-ring, but that size normally uses a 10mm diameter tube (same as a power steering hose) making it too small for the cooler. the tube where the o-ring sits is about 1/2" or 13mm diameter. I was also watching one of Leroy's youtube videos where he showed how to id the coolers vs his cooler. the spare cooler I have is in fact an OE one (has marks on the hex of the fittings) the one on the 93 truck is one of his coolers which is pipe thread.

as a temporary repair, I also found a shorter cooler (looks like a trans cooler) which has 1/4 npt thread. I might be able to run to the hardware store and get a couple of male 1/4 npt to female 1/2" npt or 1/2" flare (not sure what Leroy's hoses have on them) and cobble in that shorter cooler until I can source a replacement cooler with npt fittings or find a set of adapters with the correct size o-ring ends.

If I cobble in that shorter cooler with 1/4npt threads, will there be any issues with flow?
 
I would NOT do anything that reduces size of fitting for flow. You can go up in size then back down to original size. Going from 1/2” down to 1/4” is a huge restriction in flow. I would rather no oil cooler than that.

Always try to keep 90° to a minimum- none of possible- nice smooth long bend fittings.

This is all why I am a fan of eliminating the factory stuff. Get ya a nice quality cooler that will outperform the original and uses normal fittings. Go to a hydraulic hose shop and have hoses like you find on a Caterpillar dozer. All steel, no oring hydraulic fittings out the block. Buy once cry once - the fittings flow amazing and never fail along with the hoses. Somehow the fan hits the hoses- bye bye fan, if secured properly the hoses will be fine, new fan on an engine that never lost oil. This is what the military does on hmmwvs and it is the right answer.

When messing with the oil cooler, it is important to remember the flow chart.
Hot Oil in pan gets sucked up the pickup tube through oil pump pushed out the engine through the oil cooler back into the engine. Then to the crank shaft, rod bearings, up to the horrible designed cam bearings, lifters, pushrods to rocker arms, and finally at the very end of the oil circuit gets to your side mount turbo into the tiny clearance bearing spinning that hunk-o-metal at 10,000 rpm. Finally trickling its way back down to the oil pan to play the game again.
 
Might be safer to just get a 10an union and bypass the oil cooler till I can get one in to replace it
I would NOT do anything that reduces size of fitting for flow. You can go up in size then back down to original size. Going from 1/2” down to 1/4” is a huge restriction in flow. I would rather no oil cooler than that.

Always try to keep 90° to a minimum- none of possible- nice smooth long bend fittings.

This is all why I am a fan of eliminating the factory stuff. Get ya a nice quality cooler that will outperform the original and uses normal fittings. Go to a hydraulic hose shop and have hoses like you find on a Caterpillar dozer. All steel, no oring hydraulic fittings out the block. Buy once cry once - the fittings flow amazing and never fail along with the hoses. Somehow the fan hits the hoses- bye bye fan, if secured properly the hoses will be fine, new fan on an engine that never lost oil. This is what the military does on hmmwvs and it is the right answer.

When messing with the oil cooler, it is important to remember the flow chart.
Hot Oil in pan gets sucked up the pickup tube through oil pump pushed out the engine through the oil cooler back into the engine. Then to the crank shaft, rod bearings, up to the horrible designed cam bearings, lifters, pushrods to rocker arms, and finally at the very end of the oil circuit gets to your side mount turbo into the tiny clearance bearing spinning that hunk-o-metal at 10,000 rpm. Finally trickling its way back down to the oil pan to play the game again.
Do you have any suggestions for fittings for the 1994?

I have a kit here, I have always had issues getting the 90's in the block at the correct angle.

Am I correct that the 1994 has 3/8 not fittings out of the block?

Seems there isn't a lot of room between the block and the exhaust manifold.

I remember using several different wrenches to tighten the 90's out of the block
 
I was mistaken on the shorter cooler i have. the fittings are 3/8" npt not 1/4" I guess me looking at it in the dark isn't a good idea LOL. I wouldn't think going from 1/2" to 3/8" would be that much of an issue at least for a temporary fix.
 
That's like a 33% reduction in flow.
Very true. I just returned from the hardware store with some fittings. measured the ID of the brass 3/8" male coupling, it's a 1/16" from having a 1/2" ID. I can't say what the cooler flow is, but it's structure looks identical to the factory oil cooler other than being a little shorter.

Man o man! I took my 95 out to get the parts, you don't realize just how bad something is until you've been driving a different vehicle for a few weeks, then jump back into this one and drive!! my steering on the 95 is really out of whak!
 
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