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Anybody Have Experience Replacing R4 Compressor with Sanden

Any pointer on how to identify the bigger one?

I notice, sometimes it said LTR4?

So far, the AC works after putting 4lbs back in it.
We will see how long it last.

The 11 CU in unit has a "11" on the back casting of the compressor in 1" high numbers.

From the other thread: The A6 was a good compressor but, I have seen them get ruined (lock up) as well. I would go through the trouble to put an A6 on.
 
Here is my conclusion so far.

There is an Enhanced Sanden SD7 that cover 170cc to 210cc displacement to replace R4 180cc.
A bracket from Vintage Air.

We need to a shope to make lines to adapt the current fitting to the Sanden fittings.

The A6 have similar problem with R4 with leaky seals.
Although, they are probably still being manufactured as supposed to the R4 with only rebuilt available even if they said "new".
 
The SANDEN SD7 is a GOOD compressor. Mine lost the shaft seal so I replaced it with a standard HT6 compressor(I run a 96-99 style compressor to work on the DURAMAX), and even though the HT6 is actually rated at a slightly higher displacement, it can't hold a candle to the SANDEN at an idle. Even at an idle my SANDEN would blow ice out the vents where the stock HT6 style is OK at an idle(but blows ice running down the road). So believe all the displacement numbers as compressor efficiency isn't taken into consideration normally in those figures. Now I need to order a seal and installer so I can get my SANDEN back on and sell the HT6 stock style unit.
 
Any Pictures? I'm not even sure which one I have now.

What is the most likely point of leaks besides the Shrader valve on the compressor?

Ferm, how much did you pay for the Sanden, if you remember?

Thanks for the info, guys.

My sanden 4 years ago was $200, now they are right around $270-300. It is the SD7H15 replacement for the stock 96-02 diesel engines and 96-99 gas engines(the infamous GM HT6 belly leaker). Sandens common leak points seem to be the shaft seal behind the clutch. And GM's most common leak point is the high side service port, and is why I NEVER hook up the high side when checking them. Years back the SANDENS didn't have seal problems, but R-134A hasn't proven kind to the seals. It is a noisy compressor by comparison to the R4 or HT6, but it works VERY good at idle on up.
 
My sanden 4 years ago was $200, now they are right around $270-300. It is the SD7H15 replacement for the stock 96-02 diesel engines and 96-99 gas engines(the infamous GM HT6 belly leaker). Sandens common leak points seem to be the shaft seal behind the clutch. And GM's most common leak point is the high side service port, and is why I NEVER hook up the high side when checking them. Years back the SANDENS didn't have seal problems, but R-134A hasn't proven kind to the seals. It is a noisy compressor by comparison to the R4 or HT6, but it works VERY good at idle on up.

The AC shop I took my '99 to, installed a reman Sanden for $185. This is the first AC that I have to turn down the temp level for me, not just the wife.
 
Always wondered why the newer systems did better. Looks like the compressor design and efficiency makes a big difference. I'll have to try an Enhanced Sanden SD7 on the dual air suburban. It could use all the help I can give it.

The 93 with the VOV I can't see the need. Although reliability may tip my hand...
 
The AC shop I took my '99 to, installed a reman Sanden for $185. This is the first AC that I have to turn down the temp level for me, not just the wife.
I miss my SANDEN and need to order the seal and installer so I can put it back on. My current GPD HT6 does GREAT going down the road but is lacking at idle, the SANDEN would freeze me out at idle and going down the road I had that wonderful vapor coming from my vents because the air was so cold.
 
I am reviving my old thread from 3 years ago.

So, checking a lot of forums.
It looks like the proper Sanden replacement SD7H15HD-FLX (Model: 4864).
Apparently, the hose hook up is the same as what we have.

This is the bracket to convert from R4 to Sanden mounting:
http://www.tbiproducts.com/index.cf...oduct_id=20/category_id=3/mode=prod/prd20.htm

Using the Sanden, the refrigerant charge at lower amount.

My question is which orifice should be used?
I know there is GM Stock Orifice and some suggest using the Blue Orifice (used in Ford) less pressure.
The VOV is not suggested for the dual ac in Suburban.
 
I would use stock.

I converted my 98 with an HT6 compressor to a Sanden U4400 compressor. Was one of the best upgrades I could imagine.

I'm excited to see another version for the older harrison pumps - I would like to find some more info on that....
 
The R-4 is available in 8-11 cu ft of displacement, so be careful of remans as many out there use the 8 or 10's for there reman units. And the SANDEN SD7H15 works just fine for a dual air unit as that is what is on mine now. Also it may be noteable that 96+ trucks use a 10 cu ft output H6 compressor. Now MOST SANDEN swaps use the SD5 compressor as it is pretty compact, but it will not stand a chance at a dual A/C unit.

It would be necessary to know which Cu Inch R4, 8 CI thru 11 CI, a Suburban had on it from the factory to determine which Sanden compressor to choose. One of the member herein had asked "How do you identify which R4 you have"? Does anyone have information to determine which R4 a vehicle has?
 
I am reviving my old thread from 3 years ago.

So, checking a lot of forums.
It looks like the proper Sanden replacement SD7H15HD-FLX (Model: 4864).
Apparently, the hose hook up is the same as what we have.

This is the bracket to convert from R4 to Sanden mounting:
http://www.tbiproducts.com/index.cf...oduct_id=20/category_id=3/mode=prod/prd20.htm

Using the Sanden, the refrigerant charge at lower amount.

My question is which orifice should be used?
I know there is GM Stock Orifice and some suggest using the Blue Orifice (used in Ford) less pressure.
The VOV is not suggested for the dual ac in Suburban.
@JMJNet sorry for resurrecting an old thread. what did you end up going with on your burb? my R4 compressor has been trying to lock up on me and I was looking into doing a conversion to the Sanden SD7 along with replacing the condenser and other things. I was curious on this model you posted about since on our rigs, the valve cover and the upper intake snout going into the turbo is right there in the area.

if you went this direction, would you have any photos to show just how close and what all you had to modify to make this fit?
 
Just to post an update to this age old question while I wait for JMJNet to stop by and share his experience, I went snooping around on DP and stumbled across this same thread along with another more recent one. it seems that the regular sanden 508 and 709 compressors with bolt up as a direct fit in the same R4 brackets along with using an additional support bracket from Vintage air. the AC manifold will have to be replaced with two custom made hoses along with both fittings on the compressor end would need the charge ports.

Thanks to the legwork @56pan did here in this thread I linked. it looks like I can walk away from this R4 boat anchor and have something I don't need to replace every summer!

 
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