Anyone using the F150 Brass Blocking rings?

Rich Thomson

Registered User
Anyone personally install the F150 brass Blocking rings? Opinion or feedback. I am doing a rebuild and wanted to ask.

I purchased a set of aftermarket F150 blocking rings and they have a different thickness. I ordered a set of OEM Ford F150 Blocking rings too and will inspect them when they arrive. I have a .008 thousands differenct between the OE and aftermarket ones. Total Ring thickness is the same at .316". See picture. Anyone have experience with this. My theory is if the blocking ring teeth are shorter it's like using a set of worn blocking rings which would cause the gear to grind. My experience is as the tip of the blocking ring wears the trans tends to grind gears when speed shifting.

**** UPDATE ****

After checking all 1-4 blocking rings which are suppose to be the same I have found different tolerances with the 4 brass blocking rings. The OEM Fiber rings all were .082" in thickness.
The thickness is as follows for the Aftermarket Brass Blocking Rings:
.077"
.078"
.078"
.079"

fiber-blocking.JPG


brass-blocking.JPG
 
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I have them on my 5 speed,I got them on my car so they will last a little longer(I guess I'm to hard on the tranny).To me, they are stiffer and thus take a little longer to change gears (as long as they last)I like them.I don't recomend them for speed shifting
 
Update on the rebuild.

Seems the thickness is not going to matter. What will matter is the tooth count. Looking at the OE fiber and the F150 blocking rings I now see an important difference. The OE rings have teeth missing on the blocking ring where as the aftermarket ones do not. Fewer teeth faster engagement of gear. I have started with 3rd gear. The OE fiber ring has only one tooth missing while the OE F150 ring has 3 theeth missing. I decided to follow the F150 configuration. I identified the same teeth and grinded them away. I have not finished 5th yet but it also has three teeth missing on the OE fiber blocking ring. Reverse blocking is left alone as the aftermarket one is missing the same 6 teeth from the ring.

3rd-gear-blocking-pic1.JPG


3rd-gear-blocking-pic2.JPG


3rd-gear-blocking-pic3.JPG


3rd-gear-blocking-pic4.JPG
 
I would have thought more teeth would give you a faster engagement. My freind those rings put in years ago and the tranny shifted great with no mods. Better then stock
 
DamonSlowpokeBaumann said:
I would have thought more teeth would give you a faster engagement. My freind those rings put in years ago and the tranny shifted great with no mods. Better then stock

It's an old racer's trick to knock off every other tooth for faster engagement. I plan to try this on the next SC tranny I do.
 
XR7 Dave said:
It's an old racer's trick to knock off every other tooth for faster engagement. I plan to try this on the next SC tranny I do.

I thought I read somewhere on here that with the SC blockers you would end up with removing two beside each other when taking off every other tooth.

Shane
 
quick35th said:
I thought I read somewhere on here that with the SC blockers you would end up with removing two beside each other when taking off every other tooth.

Shane

And the problem is.... :confused:
 
How hard is it to replace the blocker rings in the M5R2? Is it something I could do my self?

Shane
 
Caution when removing teeth you need to limit the amount of teeth you remove. Too many teeth and the trans could grind and jump out of gear. All I am doing is removing the same amount of teeth as the F150 has removed on the stock blocking rings. The SC 1st, 2nd, 3rd, 4th blocking ring only has one tooth missing vs. the F150 rings. 5th has 3 teeth removed. Stock SC reverse blocking ring has 6 teeth missing my guess it that since so many teeth are removed it helps us get it into rev faster. Also you are at low RPM when you engage rev anyway.

As I am rebuilding the M5R2 I am taking pictures of the process. So far I have about $400 in special parts needed to rebuild the trans. You have to press out a few bearings just to get all the blocking rings out. I will have a new How-To article when the trans is rebuilt and added to the MN12 Performance web site later this year. Lots of pictures and shop manual step by step to the rebuild.
 
I would just think with factory cut gearset in the tranny it would be a nono...I guess if you dont go overboard...But like I said my freind never had a problem
 
I just about finished the rebuild this weekend. After checking the Input Shaft Countershaft and Thrust washer endplay I have to order shims. I should be able to get it finished by Wednesday. It took me several tries to figure out which was the best and sometimes the only way to install many of the parts in the case. I'll post more pictures of the rebuild later tonight. There are 4 shims/washers that may be replaced. Input Shaft, Countershaft, Thrust Washer and Half Washers. Some washers have to be replaced after they wear and some shimes have to be replaced if the endplay calls for it. Very important to check the endplay so the transmission lasts.

Rich

m5r2case.JPG
 
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M5R2 Shop Manual

I have created Adobe PDF files from the Ford Shop Manual on CD. The files cover the removal and breakdown of the M5R2 transmission. I transferred it to PDF in high resolution which allows for good zooming of the diagrams. :cool:

M5R2 Transmission Service Manual

Rich
 
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Rich,

Do you have any feedback on how your modifications to the the blocker rings have worked out? I see you ground off some teeth and am curious if you achieved what you thought you might by doing so.
 
Mike8675309 said:
Rich,

Do you have any feedback on how your modifications to the the blocker rings have worked out? I see you ground off some teeth and am curious if you achieved what you thought you might by doing so.

Ditto :D

Shane
 
Modifying the blocker like this does help. My second gear ring is missing everyother tooth and its an f-150 peice. I have had to replace the blocker twice now since ownership wich is about every 50k. Not bad concidering the abuse it gets. The brass rings are a bit stiffer. It requires really yanking the lever when speed shifting but you get used to it. Before going the f-150 ring route I went through 2 factory rings, if I missed the 1-2 it seemed to peel off all the friction material on the ring after only a couple times. The factory rings are a smoother shifting ring though.
I only use the brass rings on the 2nd and 3rd gear. I don't hammer 4th so this seems to work really well.
This mod was somthing I did along time ago and at the time made far less HP in my 89 sc. I recently built a 319HP 1990 cougar and after the work if you really banged the gear you got wheel spin useing the stock trans, so on a street car with limited traction and a good runing motor the only thing hitting the gear any harder is going to do is spin the tires. This will only be agravated by steeper gears. The SC now makes 390HP and speed shifting second on anything but a prepped track is a waste of time useing 3.55's.Slicks, of course, will be different.
 
The brass blocking rings worked with or without the missing teeth. The effort to shift is acceptable under 4,500rpm's above 4,500rpm's it gets difficult. 1-2nd shift: Reving the engine to 6k and it took 1k of rpm's to drop before it would go into gear. If I really forced it the gears would grind. I found a set of factory blocking rings and am currently using them in 2nd, 3rd, 4th and 5th gears. 1st gear is brass with 3 teeth missing on the ring. I can get the car to shift (1-2) at 6k now but the effort is high. Best choice would be carbon fiber but no aftermarket makes them for the M5R2.

Rich
 
F150 Blocker Part #'s

Rich, Do you have the P/N's of those F150 Blockers? I bought F150 brass blockers years ago, and they were about half the circumference of the SC blockers. The only blocker that could be used, was the Rev. blocker, and that fit the 1-2-3-4 position, but NOT the Rev. position.

I'm very aware of why the old Toploader Syncros worked, with every other tooth removed (even number of teeth on Syncro). They worked because the mating gear had twice the gap size to fall into. BUT if only a few teeth are removed, as you suggest, then the majority of the mating gear has to go through the same size small hole as the unmodified blocker. Sure, it helps those 6 or so teeth, but the rest of them must perform as designed. Please explain.

68COUGAR
 
Blocker Rings

This will date me, but I remember reading an article in a hot rod magazine in the middle 1960's concerning the removel of alternent teeth on the transmission gear synchronizers to speed up shifting, especially when not using the clutch. I tried to locate this article when my 5-speed was having the paper lined synchronizers replaced with all brass, but no joy. I sure would like to locate that article!
 
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