I just picked up a 1997 F250 4x4 7.3 5speed this weekend. I have spent a few hours searching on the google on the differences and the pros and cons of each. The overwhelming response always seems to be go with a single mass flywheel setup. I currently have a dual mass on the truck. It is making a slight scratching noise, and I am assuming it is the beginning states of it starting to go bad. Regardless, what I am trying to decide is what to go with. I like everything I have read about single mass over dual mass, except for one thing, the noise. Not everybody has mentioned it, but there is enough talk about it to be concerned. Also,my buddy on here who just swapped a 7.3 into his 96 bronco, is running a single mass setup in his, and it's almost unbearable inside. You almost can't hear other people talking in the truck it is so bad. I feel like the decibel level is high enough that if you drove it frequently, it could actually do damage. He has said he thinks he might switch to a dual mass because of it. I have read on another forum that if you add an extra quart to the transmission, that reduces a lot of the noise. My main concern would be my truck becoming as loud as his truck is. If it got louder than it is now, that wouldn't be an issue, but if it got as loud as his, I would probably rather run a dual mass than a single mass. The noise level is that bad in his.

Anybody encounter this problem and then found a good solution for it? Since his was a swap, I think he is missing some boot for the transmission which he said is a huge part of it, and I don't think he has any shielding. So I don't know how much that helps. Also, has anybody used some sort of sound deadening material and placed it around the transmission and see if that helps? I would love to do a single mass, but hearing what it could potentially turn out to be, kind of makes me nervous to do it.

 

Hi B-Rad88. I am digging through the same information that you did when you posted this, and I am trying to make a decision between the SMF and the DMF as well. I see that there are no replies to this post, but I am wondering which direction you went? And how did that turn out for you? I appreciate the input!

 

I went with the SMF set from LUK off Rock Auto. It wasn't too bad of a job. It has everything you need to change to a dual mass. It's not so much a conversion in my opinion because you don't have to modify anything to make it fit. You just simply remove all the old dual mass stuff and put the single mass stuff in.

There is some gear roll over noise that many have mentioned. Some have success with overfilling the transmission s little bit. Mine isn't that bad. The noise my buddy had ended up being the firewall so you shouldn't have these issue. My truck is very loud on the inside though. My exhaust and injectors tunning make it almost impossible to hear people inside my cab so the gear roll over noise isn't an issue for me.

I have been reading a lot of bad things recently about Southbend so I'd look into that more if you go with them. Valair seems to be a great deal despite it being more than the LUK setup. Honestly, unless you are planning on going more than 400HP, the LUL setup is probably the best bang for your buck. I think I have about 12,000 on it by now and no slipping. I'm running stage 1 injectors and tunes from DP. I'm probably baelu over 300 HP though.

The clutch is about 50% easier to engage and disengage, so sitting in bumper to bumper traffic is nowhere near as bad. So your legs will be happy.

 

Thanks a bunch for the great response B-Rad! My truck is already pretty loud in the cab, so I think that any extra gear roll over noise won't contribute too much more.

I have decided on the Valair SMF kit with a new solid flywheel. I've heard nothing but good things about the company and their products. A bit more than the LUK, as you mentioned, but we'll give 'er a try. Not necessary due to my stock HP rating, so maybe overkill. But cheaper than having somebody do the work for me

The synchros are starting to go on 2nd & 3rd (I've read that is fairly common), so I think a rebuild will be happening sometime in the next year or so. Fun stuff, I just wish I had a backup vehicle while the truck is out of commission. Time for another truck??? I'll go ask my wife...

But then again, forgiveness might be easier than permission.

 

Where are you located? I'm going to be selling mine. I just bought an 01 F350 and going to be selling the 97 F250.

 

I'm in the middle of WI where rust knows no bounds I'm gonna hold off on that rebuild project for as long as I can... so much to get done around here! Thanks for the heads up, though!