Power Steering Pump Differences

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Doppleganger

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I am having a major blonde moment. Had this figured out a couple years ago, now cant figure out what I did. My truck is an 85 - still has the original steering box, but the PS pump is a 97 style. For some reason I picked up 3 different PS lines. I no longer have the original 85 PS pump, so cant tell the differences between routing or line styles. I need pics of the rear of an 85 and a 97 style to figure out the differences. The 97 style has 1, with a port for a second. No idea what the 85 style has.

Trying to find out if the high pressure line on both the 85 and 97 have the same threaded ends.

There's nothing older than 94 in the local yard so nothing I can compare to.
 
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Doppleganger

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Re-worded this a bit. Bottom line is I'm trying to find out if the high pressure line on both the 85 and 97 have the same threaded ends at the power steering pump.

There is a bracket for the back of the 97 pump and I cannot figure out WTF its for.
 

bucket

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Iirc, the fittings are the same size. The '96-up serpentine setup used a support bracket on the backside of the pump, just for a little extra support.
 

Doppleganger

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UPDATE - not that anyone really gives a ***, but here's the main difference I was asking about. My 85 PS lines are pretty simple and straight(er) to the steering box. The 97 lines that go to my PS pump, are bent very odd and erratic in comparison - unusuable with the 85 box. Went to the JY today and checked out a 98 truck. Apparently (unbeknownst to me) the 85 vs 97 Saginaw gear boxes are on opposite sides of the frame. This is why my 97 pre-bent PS lines wont work. So it looks like I'll be taking 2 and making one for it. You all may have known this - I did not.

85:
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97:
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bucket

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UPDATE - not that anyone really gives a ***, but here's the main difference I was asking about. My 85 PS lines are pretty simple and straight(er) to the steering box. The 97 lines that go to my PS pump, are bent very odd and erratic in comparison - unusuable with the 85 box. Went to the JY today and checked out a 98 truck. Apparently (unbeknownst to me) the 85 vs 97 Saginaw gear boxes are on opposite sides of the frame. This is why my 97 pre-bent PS lines wont work. So it looks like I'll be taking 2 and making one for it. You all may have known this - I did not.

85:
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97:
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Yeah, but your '97 pump should work fine with your '85 lines in your '85 truck. The only real difference in pumps was whether or not it was hydroboost. Hydroboost brakes had two returns on the pump.
 

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Yeah, but your '97 pump should work fine with your '85 lines in your '85 truck. The only real difference in pumps was whether or not it was hydroboost. Hydroboost brakes had two returns on the pump.
Some of those older style pumps had 2 stubs coming off of them - for pressure and return (both for just a hose and clamp). The 97 has a threaded port for the pressure line. That threw me a bit also. I ordered the full 85 style pressure line so hopefully that fixes that. I found a return line thats just the steel end at the steering box - the rest is just a hose and 2 clamps.

At my blonde moment I was holding 3 lines; 2 from a 97 (pre-bent in odd ways) and the "pressure" line from the older style that consisted of a 10" straight steel pipe with a fitting (at the pump end) that you have to bend yourself, but nothing on the gear box side. Seems stupid simple now. lol

Thanks again. :hat:
 

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The pressure hose never has just a hose barb, it would blow right off. Those pumps with two nipples are for a hydroboost truck, both of them are return fittings.
 

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Update: so the pressure line for a 97 and an 85 are night-day different. Trying to use an 85 line with a 97 pump or a 97 line in an 85 truck doesnt work as both have interference issues with the other. I took the 85 and 97 line down to a place that makes any hose you want. He cut the end off the 85 and swapped/crimped/brazed the 97's on. Looked perfect but the back of the 97 end still interferes with the cross member. So now am going to see if they can shorten the line at the port a bit - still looks like the line will have to be installed on the pump before installing it in the truck. This project is so not worth it.
 

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Update: so the pressure line for a 97 and an 85 are night-day different. Trying to use an 85 line with a 97 pump or a 97 line in an 85 truck doesnt work as both have interference issues with the other. I took the 85 and 97 line down to a place that makes any hose you want. He cut the end off the 85 and swapped/crimped/brazed the 97's on. Looked perfect but the back of the 97 end still interferes with the cross member. So now am going to see if they can shorten the line at the port a bit - still looks like the line will have to be installed on the pump before installing it in the truck. This project is so not worth it.
Well in the pic of steering box one is 2 wheel drive and one is 4 wheel drive, That may be the driffent.
 

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Update: so the pressure line for a 97 and an 85 are night-day different. Trying to use an 85 line with a 97 pump or a 97 line in an 85 truck doesnt work as both have interference issues with the other. I took the 85 and 97 line down to a place that makes any hose you want. He cut the end off the 85 and swapped/crimped/brazed the 97's on. Looked perfect but the back of the 97 end still interferes with the cross member. So now am going to see if they can shorten the line at the port a bit - still looks like the line will have to be installed on the pump before installing it in the truck. This project is so not worth it.
I can’t remember what I did but it wasn’t very complicated IIRC.

I’ll get some pictures in a bit.

Also, the GMT400 has the gear box inside the frame because the frame is about a foot wider than the squares. Square has narrow frame & saddle bag gas tanks, late 90’s had a great big tank inside the frame rail, and 4x4 IFS needed the wider frame so the control arms would not be too long.
 

CalSgt

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@Doppleganger Here’s mine, ‘98 pump on ‘80 K-10. I know you abandoned the L31 brackets but the pump should be in the same spot.

Let me know if there’s any specific angles you want to see

I think I just made my own return line and added a bit of a loop so it would be long enough to allow a little frame to engine flexibility for chassis movement and motor mount torquing.

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CalSgt

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I searched through all my summit and Oreiley purchases and found which high pressure line I used. Looks like it’s an 81 to 87 V8 stock high pressure line.

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Doppleganger

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I searched through all my summit and Oreiley purchases and found which high pressure line I used. Looks like it’s an 81 to 87 V8 stock high pressure line.

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No idea how you got that one to fit - that ?-looking end was orientated backwards to the pump when I tried it.

The grafted end on there now (97) has what looks like an upside down L. I need to shorten the horizontal part by about an inch and it would fit and route perfectly. My other Plan B was to have them shorten the pump side part of the line to about an inch, then connect it to the over-the-frame part with a braided SS line.

Thanks a bunch for the pic - need to lighten it to see how you got it in there.

EDIT: your pump is slightly different from mine. Mine has a return tube from the back to the side - totally in the way of the HP twisted hose end. I'll get a pic.
 
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