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Im currently installing a T5 into my 67 mustang, i used the Ron morris products cross member with my old c4 transmission mount. Everything has bolted up perfectly without having to force anything, but i noticed that my fan now has a clearance issue with the upper radiator hose. During the t5 swap i replaced my worn out motor mounts and im wondering if my issue is a combination of the old tranny mount with the new motor mounts, or if i need to add shims between the cross member and the mount in order to rotate the front of the motor down. Any advice would be awesome, and let me know if theres something i'm totally missing
 

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The problem is that the T5 is a taller transmission then the C4 or Toploader. If used with the stock cross member the T5 is going to hit the transmission tunnel. The conversion T5 transmission bracket has more of an offset which lowers the transmission. While giving the needed clearance, it also changes the angle of the engine/transmission. Some people have had issues like yours or have had issues with the carb/air filter hitting the hood or drive line vibration from alter universal joint angles. Off hand, I'd say play with the fan spacer.
 

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I had enough room to shim mine up about 1/4". Got it very close to stock. The body of the shifter misses the crossmember about 1/16".

If the body of the shifter is hitting the crossmember then get a set of the TCP motor mounts. They allow you to slide the motor fore and aft. Move it back enough so that the shifter body clears the crossmember.
 

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68RCodeConv said:
I had enough room to shim mine up about 1/4". Got it very close to stock. The body of the shifter misses the crossmember about 1/16".

If the body of the shifter is hitting the crossmember then get a set of the TCP motor mounts. They allow you to slide the motor fore and aft. Move it back enough so that the shifter body clears the crossmember.
This is a lot what I did, but I made my own bracket from a stock C4 bracket. I slotted it front to back for the bolt holes, dropped it about 3/4" straight down, then used shims to bring the assembly up so it just barely doesn't touch the body.

Remember also, if you do any movement of the motor to the rear...BE ABSOLUTELY SURE TO CHECK YOUR DRIVESHAFT CLEARANCE to the transmission tailshaft. It's a close thing with a T5 conversion to begin with.

Cris
 

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The only way to get close to the original 3 degree driveline angle with the T5 conversion is to notch the upper trans crossmember in the tunnel and move the trans up about 1/2" to 3/4". I did this (cut out almost 2 inches) and shimed up the trans 1/2" to get the driveline angle to about 3.5 degrees. This won't weaken the trans tunnel or upper trans crossmember because there are spot welds adjacent to the notch that you have to cut out.

Forgot to mention that I used a lower crossmember from Modern Driveline. Other makes will result in the same thing unless they instruct you to notch the upper crossmember...haven't seen one yet. Without notching and shimming up the T5, my fan was hitting the top of the shroud. Why they don't seem to mention this is beyond me.
 

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Not to hijack, but is it necessary to correct the "stock" driveline angle when doing a T5 conversion? I put a T5 into my '65, and it's recently developed an awful vibration that it never had when I first did the conversion.

This is the first I've heard about needing to correct the driveline angle; I didn't realize everything was thrown off that far from stock when using a T5.
 

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Put an angle finder gauge on the trans output shaft, or vertically positioned ears of the trans end driveshaft yoke and then minus 90 degrees. Three to four degrees (down) is your goal.

Do the same thing for the pinion end, but statically the pinion angle should be 0.5 degrees less than the trans angle.
 

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Huskinhano said:
The problem is that the T5 is a taller transmission then the C4 or Toploader. If used with the stock cross member the T5 is going to hit the transmission tunnel. The conversion T5 transmission bracket has more of an offset which lowers the transmission. While giving the needed clearance, it also changes the angle of the engine/transmission. Some people have had issues like yours or have had issues with the carb/air filter hitting the hood or drive line vibration from alter universal joint angles. Off hand, I'd say play with the fan spacer.
blkfrd said:
The only way to get close to the original 3 degree driveline angle with the T5 conversion is to notch the upper trans crossmember in the tunnel and move the trans up about 1/2" to 3/4". I did this (cut out almost 2 inches) and shimed up the trans 1/2" to get the driveline angle to about 3.5 degrees. This won't weaken the trans tunnel or upper trans crossmember because there are spot welds adjacent to the notch that you have to cut out.

Forgot to mention that I used a lower crossmember from Modern Driveline. Other makes will result in the same thing unless they instruct you to notch the upper crossmember...haven't seen one yet. Without notching and shimming up the T5, my fan was hitting the top of the shroud. Why they don't seem to mention this is beyond me.

I've been researching various 5 speed conversions for a while now, and I've never heard of this kind of issue with a T5 before. Tremecs yes, but never T5s. Thanks for the information fellas; it may help me and others.
 

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If you swapped engine mounts, you might 68-up style mounts. I think if you use these on 67 frame stands the engine would sit up higher than normal.
 

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mavken said:
Huskinhano said:
The problem is that the T5 is a taller transmission then the C4 or Toploader. If used with the stock cross member the T5 is going to hit the transmission tunnel. The conversion T5 transmission bracket has more of an offset which lowers the transmission. While giving the needed clearance, it also changes the angle of the engine/transmission. Some people have had issues like yours or have had issues with the carb/air filter hitting the hood or drive line vibration from alter universal joint angles. Off hand, I'd say play with the fan spacer.
blkfrd said:
The only way to get close to the original 3 degree driveline angle with the T5 conversion is to notch the upper trans crossmember in the tunnel and move the trans up about 1/2" to 3/4". I did this (cut out almost 2 inches) and shimed up the trans 1/2" to get the driveline angle to about 3.5 degrees. This won't weaken the trans tunnel or upper trans crossmember because there are spot welds adjacent to the notch that you have to cut out.

Forgot to mention that I used a lower crossmember from Modern Driveline. Other makes will result in the same thing unless they instruct you to notch the upper crossmember...haven't seen one yet. Without notching and shimming up the T5, my fan was hitting the top of the shroud. Why they don't seem to mention this is beyond me.

I've been researching various 5 speed conversions for a while now, and I've never heard of this kind of issue with a T5 before. Tremecs yes, but never T5s. Thanks for the information fellas; it may help me and others.
Me neither...

I have my conversion 80% complete and I'm fixin to have the car on the ground moving on it's own in the next couple of weeks.

You guys have me concerned now that I overlooked something...
 

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I had vibration problems when my T5 was angled down so that it would clear the transmission tunnel brace. I had the drive shaft rebalanced did not help.

I ended up notching the brace so I could get back to the original angle. Vibration gone. I reinforced the top of the tunnel where I cut back the brace.
 

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I put a little over 1,500 miles on the original conversion with the I-6. I shimmed the rear end to match, and had no vibrations.
The drive train angle with the I6 was 4 degrees.
With the V8 installed and the engine lowered (about 5/8"), I'm back to just a hair over 3* without notching the convertible tunnel brace.
 

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daroberts67 said:
with my old c4 transmission mount.
Dollars to donuts thats your problem. Either your crossmember is way off or your old mount is lower than the T5 specific mount.
 

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66_Runt said:
I put a little over 1,500 miles on the original conversion with the I-6. I shimmed the rear end to match, and had no vibrations.
The drive train angle with the I6 was 4 degrees.
With the V8 installed and the engine lowered (about 5/8"), I'm back to just a hair over 3* without notching the convertible tunnel brace.

Scott,

How did you lower the engine? Ron Morris mounts?

Thanks,
-Shannon
 

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A C4/toploader/T10 transmission mount will work well. Old (used) mounts may cause the vibration you describe. Also, check for any rubbing or interference with the transmission and tunnel. My main interference was the shifter housing (aftermarket) and the front of the stock shifter hole. I had to grind my shifter hole a little.

I'm in the last phase of installing an aluminum driveshaft, and will report back how that works. I had a low-level vibration off and on at certain speeds (I think it was DS-related, but it wasn't consistently there). We'll see. :)

Daniel
 

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If the fan is hitting the upper rad hose, it would indicate the trans is sitting to low in the back. How much room is there between the top of the trans and the tunnel right near the shifter opening? I would guess that the RM mounts are likely made on some type of jig and shouldnt be that far off. Perhaps it a T56 or AOD cross member? Do you have a picture of the cross member?
 
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