I read numerous times here that a Dewitts radiator was a nice upgrade. So, I ordered their radiator/fan combo for my 98 C5 Auto LS3. It was the cut down version for S/C vehicles. It was not too bad installing, until I realized that the passenger side hose outlet was welded 1" lower than my factory radiator. I think I was able to raise it enough to clear my frame but, I am not sure. I am unsure because the hose bibs that they tigged on were too large in diameter and no matter how hard I pushed that hose, it would not slip over the lip. I measured my factory fittings and compared them to the Dewitts, and the Dewitts are definitely larger. After over-nighting this from Summit, I am dead in the water because I can not find a hose to fit. If anyone has an answer, I would be grateful to hear it. Thanks in advance

 

The inlet/outlets are made from standard aluminum tubing, which is only available in inch sizes. This radiator uses 1.38" connections which is 35mm. The connections on the stock radiator are plastic and molded at 1 5/16" (33mm) and this difference hasn't presented a problem. DeWitts use to make this with 1.25" tube (31mm) and some complained it was too loose so it was switched to 1 3/8".

 

Thank you for that quick response, it means a lot.
The thing is that we tried using the old hoses which were only about 10 months old, but neither the mechanic or I was able to get them on. He then had new hoses delivered, and we could not get those on either. I am at a loss as to what to do. Before I go to bed, I decided to place the handle of a tool I had laying around into the end of the old hose in a very tight fit. I then heated it up as much as I thought would be safe, and I am hoping that in the morning, it will be expanded enough to install. I am sure that you have not had complaints about this before, because I have read numerous good ratings before I went with Dewitts, I was just hoping that you knew a trick, or the radiator was mislabeled, etc. but, it just will not go on, and tomorrow will be 3 days just trying to put the hoses on. My son came to pick me up because I thought I would be driving home, and even he, who can bench press over 480lbs could not push it on.
Thank you again for your reply, if you have any ideas as to what is going on, please let me know.

 

try using water mixed with a tad of dish soap on the inside of the hose

 

@aahrested Is the 1" lower placement normal? Regarding their size, did you verify if yours are only 1.75mm larger as mentioned above?

Could this be a possibility?

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Wow. Just came here to do a search for the fitment of Dewitt radiators. Almost bought one yesterday and came across this thread.

Please let me know what happens here. I though dewitts was suppose to be the best in the business. There shouldn’t be any problems with hoses fitting especially older hoses since those are usually much looser than brand new hoses.

could you post some photos so we can get an idea of what we are looking at. Hopefully Dewitt just sent you the wrong radiator or maybe followed the wrong manufacturer instructions.

just read their website. It says direct fit replacement. One would assume that the hose fitting are identical to oem. Is this right @Tom DeWitt ??

 

No need to worry tommyallen, go ahead and buy one. As it turns out I decided to try again with a different brand of hose so, I bought a pair of "Gates" hoses first thing this morning, and I could not believe it, they fit fine. I do not know what the other brand was, that my mechanic ordered but, then returned. I think they were NAPA, like my old ones. You could see the difference in diameter easily. That's odd too, because I always thought Gates made them for NAPA. I installed a lift in my garage, swapped the LS3 in place of the LS1, had the entire back end apart for trans & diff replacement, performed numerous muscle car frame off restorations, but I NEVER spent 3 days trying to install a water pump hose until now.
I'm embarrassed that this happened, and apologetic to the Dewitts whose radiator appears to be fantastic but, who would have thought that it was the hose, and not the radiator.

 

I've had excellent experience with my Dewitts Radiator. It installed easily and with the SPAL fans keeps me running cool. The one small complaint I have is that the fans are loud. But then again I have twin Turbos so I don't really hear the fans unless I'm stopped.

 

yeah. That seems to be the major complaint ie that the fans are super loud. Probably better off sticking with oem fans.