Notices
Pre-Power Stroke Diesel (7.3L IDI & 6.9L) Diesel Topics Only

flywheel question

Thread Tools
 
Search this Thread
 
Old Jul 24, 2007 | 07:36 PM
  #1  
gonecrazyi's Avatar
gonecrazyi
Thread Starter
|
Senior User
Joined: Jul 2006
Posts: 302
Likes: 0
flywheel question

I am in need for a replacement fly wheel for my 89 f250 7.3. I believe that it is a dmf. I tends to rattles at idle and is beginning to become worse. What is the most cost effective and dependable way to go. I want to replace the clutch when I have the tranny out. I was looking at the smf conversion. I cant afford what most companies want for a kit with the flywheel, clutch and all the goodies that go with it. What do you guys think of the Luk smf conversion. Is it worth the money or can I replace the dms flywheel and clutch setup for less. Any help would be appreciated.
 
Reply
Old Jul 24, 2007 | 09:38 PM
  #2  
PLC7.3's Avatar
PLC7.3
Post Fiend
Joined: Nov 2004
Posts: 5,638
Likes: 1
From: Manitoba
Some have found NIB dual mass for well below cost on Ebay....... many others have moved up to the LUK....... Rollover noise in the trans is a side effect of the LUK other than that many are happy.

Here is some info on the LUCKY MOD........

NOW FOR THE FIX


Changing a Dual-Mass to a Single-Mass Flywheel


When taking out the flywheel be careful as this thing is heavy, around 65lbs

One thing if for any reason you have any concerns don't try this . This is at your own risk, Mel Agne (TDS/OBN) has done this conversion and so far it has worked out great, I have not put this in my truck as of yet but have it ready as my flywheel is making noise and I have this ready when I do change the clutch out I will change this out also. I am not afraid of using this fix, I feel really safe doing this to my truck.

I strongly suggest you drill out the bolt holes on a GOOD drill press to make sure the holes are straight. It would not be a bad idea to check the balance after putting it back together before installing it.

There is a guy on E-Bay that has made a DMF hub that dose the very same thing I have done and he wants $200 plus shipping for the hub, that is where I got my idea and tore a flywheel apart and discovered this trick This fix will cost you whatever the price of the 6 grade 8 X 2" fine threaded bolts & lock nuts and about an hour of your time drilling out the holes and bolting it all back together once you have the flywheel out.

After removing the flywheel take it all apart and I do mean all apart, remove everything, springs, friction plates and take the hub that bolts to the crank off, 2 small countersunk screws and remove everything in there also, there are some friction plates in it also.

The part that the pressure plate bolts to, the clutch plate, has 6 holes in the center that also bolts to the flywheel hub, this hub has 6 blind threaded holes that needs to be drilled all the way through I drilled them out to 3/8 even though they were threaded, I thought 3/8 X 2" fine threaded grade 8 bolts would be the right size and would match the holes in the ring gear plate better. , becareful when removing the hub plate that has the blind threaded holes as it is mounted to a center that is a roller bearing and you might pull the bearing apart. If indeed you do pull the bearing apart you will need to put the ball bearings back in as to line up everthing. Don't worry about the bearing as it will serve no purpose after you bolt the whole thing together.

If you notice on the plate that has the ring gear there are 9 holes drilled through it. 6 of the holes are smaller and will almost line up with the 6 in the hub you just drilled, you now have to drill the holes in the ring gear plate to match the ones in the hub you just drilled. I did this by bolting the 2 part hub back together on the ring gear plate so the clutch plate would line up true and then put 3 smaller diameter bolts, 5/16" bolts through every other hole I drilled out in the hub and through the smaller holes in the ring gear plate to line every thing up. I ran a 3/8 drill down to drill out 3 of the holes in the ring gear plate, I then put the 3/8 bolts in the 3 holes I just drilled out and tightened them then drilled out the other 3 holes. I put all grade 8 bolts in and used lock nuts, but do not use the ones with plastic in them but all metal locknuts, tourque the nuts to 40 lbs.

The 9 bolts that bolt the flywheel to the crankshaft also goes through the ring gear plate and the clutch plate, the hub now bolts to the ring gear plate so everything is bolted together to make it a single mass.
No more noise and you can still use you stock clutch setup. Hope this is of some value to you. Let me know if you use this and how you like it.
If you have any questions please fell free to ask.

Info re clutch too...........

Your decision on which flywheel should be made with great care..About a year ago I replaced my dmf with the LUK clutch and flywheel from Southbend Clutch In Indiana. With the new clutch they sent, was some info papers that I found very informative.."1. The DMF has a free travel section that reduces gear rattle in neutral. 2.The DMF has a series of damper springs on the backside of the flywheel that isolate damaging engine torsionals from the transmission and drive train. The series dampened clutch used with solid flywheels also has design elements that protect the transmission from damaging engine torsionals and reduce gear rattle. Series dampened clutch dics do NOT have a slip joint for spike torque protection. These dics are designed to fail and will fail if torque spikes exceed the rated torque capacity of the vehicle." Examples of conditions where vehicle torque ratings can be exceeded are;1. towing loads heavier than the rated vehicle load capacity. 2. High speed downshifts. 3.Coasting down hill with the transmission in too low of a gear. 4. Increasing the boost pressure on turbo applications."----Rob
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
bluemtn95ford
1987 - 1996 F150 & Larger F-Series Trucks
21
Jun 15, 2015 08:08 PM
Country_boy_2007
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
36
Mar 2, 2015 10:36 PM
baker1983
1994.5 - 1997 7.3L Power Stroke Diesel
3
Nov 7, 2012 12:02 AM
89nolaf250
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
8
Jan 31, 2010 01:37 PM
Mr. Bob
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
52
Aug 26, 2007 10:02 PM




All times are GMT -5. The time now is 07:18 PM.

story-0
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-1
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-2
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-3
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-4
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-5
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-6
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-7
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-8
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-9
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE