T-56 Magnum Hell

[amurray7777]

Hey All:

I have an 03 Terminator. When I got the car the stock t-56 was shot. I replaced it with a T-56 Magnun and 26 spline input shaft with McCleod RXT. The transmission lasted 400 miles before I started getting input shaft noise in the shifter. Returned it to summit and do one new locally. It whined slightly from day one. You can hear the input shaft whine under light load and it goes all the at up with RPM.

Everyone I’ve spoken to says you have to dial indicate the bell housing, which was not done by my mechanic. Now 8k miles later it’s getting louder and I’m hearing whirring in between 1-2 and 3-4 shifts. In 4,5,6 deal quiet.

I finally found a shop who is willing to pull it, send it out to Tick for rebuild. I’m sue my I out shaft, cluster gears and Hod now what else is already roasted. I changed the fluid at 500 miles and it was slightly dark.

How can these damn things be so sensitive to not being fill indicated? It’s the stock bellhousing. I love the fact that because it was most like installed incorrectly, I know have to pay to pull it, send it to tick for a rebuild and then have it put back on by a be shop properly indexed. My mechanic says dial indicating is bs. Everyone else seems to disagree. Anybody have any experience with this nightmare? I know a lot of us have done the swap. Any advice would be very much appreciated. The damn whine so so loud it sounds like a blower and I already have one of those. It’s getting louder lately. I’m so pissed off. I hate spending money twice.

 

[01yellercobra]

I was about to ask what disinviting a bellhousing meant. Then I read the rest of your post. Find another mechanic. Indexing the bellhousing is a thing. Though generally not at our level.

Did you clearance the transmission case for the RXT? My understanding is the ribs need to be notched in order for the clutch fork to have enough travel with the RXT set up. If the clutch isn't set up right it'll cause other issues.

 

[DSG2003Mach1]

I was about to ask what disinviting a bellhousing meant. Then I read the rest of your post. Find another mechanic. Indexing the bellhousing is a thing. Though generally not at our level.

Did you clearance the transmission case for the RXT? My understanding is the ribs need to be notched in order for the clutch fork to have enough travel with the RXT set up. If the clutch isn't set up right it'll cause other issues.

Ya but there’s no offset dowels for us. My scattershield is off a hair, starter makes a little noise when retracting but not other issues so far

 

[amurray7777]

Ya but there’s no offset dowels for us. My scattershield is off a hair, starter makes a little noise when retracting but not other issues so far

My damn trans whines like a bitch. Idk wtf to do

 

[amurray7777]

I was about to ask what disinviting a bellhousing meant. Then I read the rest of your post. Find another mechanic. Indexing the bellhousing is a thing. Though generally not at our level.

Did you clearance the transmission case for the RXT? My understanding is the ribs need to be notched in order for the clutch fork to have enough travel with the RXT set up. If the clutch isn't set up right it'll cause other issues.

Don’t know. Didn’t do the work myself.

Ya but there’s no offset dowels for us. My scattershield is off a hair, starter makes a little noise when retracting but not other issues so far

There are now dowels for us? So how is it done?

 

[03' White Snake]

No issues with my magnum except the damn seals under the shifter. Swapped that out for a tick shifter and it’s fine now.

I did what Bob said and clearanced the webbing for clutch fork clearance for the RXT.

Are you 100% sure it’s not driveshaft, u joint or rear end noises/vibrations you are feeling? Drive shaft needed to be shortened and different yoke installed, was it balanced correctly?

 

[amurray7777]

My damn trans whines like a bitch. Idk wtf to do

No issues with my magnum except the damn seals under the shifter. Swapped that out for a tick shifter and it’s fine now.

I did what Bob said and clearanced the webbing for clutch fork clearance on the RXT.

Are you 100% sure it’s not driveshaft, u joint or rear end noises/vibrations you are feeling? Drive shaft needed to be shortened and different yoke installed, was it balanced correctly?

Yeah did all that. It’s 100% coming from I out shaft. Second transmission to do it. Idk wtf is going on

 

[amurray7777]

No issues with my magnum except the damn seals under the shifter. Swapped that out for a tick shifter and it’s fine now.

I did what Bob said and clearanced the webbing for clutch fork clearance on the RXT.

Are you 100% sure it’s not driveshaft, u joint or rear end noises/vibrations you are feeling? Drive shaft needed to be shortened and different yoke installed, was it balanced correctly?

I’m getting ready to give up on this problem. It’s so annoying.

 

[amurray7777]

I was about to ask what disinviting a bellhousing meant. Then I read the rest of your post. Find another mechanic. Indexing the bellhousing is a thing. Though generally not at our level.

Did you clearance the transmission case for the RXT? My understanding is the ribs need to be notched in order for the clutch fork to have enough travel with the RXT set up. If the clutch isn't set up right it'll cause other issues.

Like what other issues? I’m about to give up on this damn carbon so frustrated

 

[amurray7777]

Like what other issues? I’m about to give up on this damn carbon so frustrated

My mechanic has done hundreds of them. I assume he knows this stufff. So idk what th hell so going on.

 

[03' White Snake]

I’m a betting man, and having 2 bad magnums seems like a hell of a coincidence to me. I’d be checking for something else.

How do you 100% know it’s the input shaft? Was the scatter shield installed and correctly?

Is your clutch adjusted correctly? Is it the throw out bearing? Look in the inspection cover, remove the clutch cable, is the TB touching the PP fingers when you pull the fork all the way back? Look if the TB is installed correctly on the fork.

Did you check the transmission is not rubbing on the floor/tunnel? That is the first place I’d be checking. Any vibration on the body from the trans would be magnified drastically into the cabin area. To install the magnum in these cars you need a BFH to message the tunnel for clearance in a few locations. Check the shifter bolts are not hitting either. I changed mine out to button heads for clearance.

Also depending on what trans cross member you are running (solid mount, Stifflers, modified stock mount) could also be contributing to these noises or tunnel interference too.

 

[amurray7777]

I’m a betting man, and having 2 bad magnums seems like a hell of a coincidence to me. I’d be checking for something else.

How do you 100% know it’s the input shaft? Was the scatter shield installed and correctly?

Is your clutch adjusted correctly? Is it the throw out bearing? Look in the inspection cover, remove the clutch cable, is the TB touching the PP fingers when you pull the fork all the way back? Look if the TB is installed correctly on the fork.

Did you check the transmission is not rubbing on the floor/tunnel? That is the first place I’d be checking. Any vibration on the body from the trans would be magnified drastically into the cabin area. To install the magnum in these cars you need a BFH to message the tunnel for clearance in a few locations. Check the shifter bolts are not hitting either. I changed mine out to button heads for clearance.

Also depending on what trans cross member you are running (solid mount, Stifflers, modified stock mount) could also be contributing to these noises or tunnel interference too.

I agree with you. I’m stumped.

 

[amurray7777]

I made a video. Have to post it to YouTube to get it on here. November 6, 2025

I’m a betting man, and having 2 bad magnums seems like a hell of a coincidence to me. I’d be checking for something else.

How do you 100% know it’s the input shaft? Was the scatter shield installed and correctly?

Is your clutch adjusted correctly? Is it the throw out bearing? Look in the inspection cover, remove the clutch cable, is the TB touching the PP fingers when you pull the fork all the way back? Look if the TB is installed correctly on the fork.

Did you check the transmission is not rubbing on the floor/tunnel? That is the first place I’d be checking. Any vibration on the body from the trans would be magnified drastically into the cabin area. To install the magnum in these cars you need a BFH to message the tunnel for clearance in a few locations. Check the shifter bolts are not hitting either. I changed mine out to button heads for clearance.

Also depending on what trans cross member you are running (solid mount, Stifflers, modified stock mount) could also be contributing to these noises or tunnel interference too.

November 6, 2025

Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.

youtube.com

 

[biminiLX]

Send it to Tick for a rebuild and put a new clutch in it. They need a FULL four quarts. I’ve burned one up but from what I read:
First trans made noise and was replaced by a new one from Summit.
That is the current trans having this issue and you plan to send it to Tick for a rebuild?
Sorry trying to help as I’ve put in 2 Magnum XLs in my s197
-J

 

[biminiLX]

I made a video. Have to post it to YouTube to get it on here. November 6, 2025

November 6, 2025

Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.

youtube.com

Does it continue as you cruise out the gears like third? Highway? First sounded pretty bad there.
-J

 

[01yellercobra]

One bad transmission, could be a bad unit. Two bad transmissions, its not the transmission. How underfilled was it? You didn't answer about the ribs being clearanced.

I'd still find a new mechanic.

 

[amurray7777]

One bad transmission, could be a bad unit. Two bad transmissions, its not the transmission. How underfilled was it? You didn't answer about the ribs being clearanced.

I'd still find a new mechanic.

It was never under filled. Idk about the ribs and I found a new mechanic.

 

[amurray7777]

Send it to Tick for a rebuild and put a new clutch in it. They need a FULL four quarts. I’ve burned one up but from what I read:
First trans made noise and was replaced by a new one from Summit.
That is the current trans having this issue and you plan to send it to Tick for a rebuild?
Sorry trying to help as I’ve put in 2 Magnum XLs in my s197
-J

The one on there is from promotion performance in Ft. Lauderdale. That is the current trans in the video having the issue.

 

[03' White Snake]

It was never under filled. Idk about the ribs and I found a new mechanic.

Not sure how you can underfill it, there is a drain hole and fill hole. You fill it until the fluid comes out the fill hole and done. It is not rocket science.

 

[SuperCharged_Coyote]

Maybe they went with the factory specs for a Mustang MT82 instead of the Tremec and underfilled it by a quart.