Another question regarding my 4 speed conversion..

I am having an issue with the transmission yoke hitting the floorboard of the car! I have a new autogear M22W hanging on the back of a 396 and Lakewood explosion proof bellhousing.

The yoke and driveshaft is what was in the car when I bought it (car had a 350/TH350 trans)..and it was my impression that the yoke and driveshaft would fit right back in place with no issues.

I noticed at the time I installed the driveshaft in the M22 that the yoke was grazing the bottom of the floor a bit (I could hear it it when I spun the tires). I found that previous owner may have welded the floor in the area of the yoke and there appeared to be some globs of weld hitting the yoke.

I initially ground off what I could, so that the yoke did not hit the floor when the car was on jackstands. Driving the other day, it started to hit really bad (intermittantly). I subsequently ground some material off the yoke..and today under normal driving conditions it was ok..but I heard it hit again when I really got on it.

Are there different yokes available that are closer in width to the driveshaft? There really isnt much clearance between the yoke and the floor (cant really get my fingers in between yoke and floor). I have 3 different trans mounts here, and they were all the same height within about 1/16" (I am now using the shortest of them)..are there different trans mounts available that would allow me to drop the tail of the trans down 1/4"-3/8" ? Has anyone modified a trans mount to lower the tranny?

The crossmember is installed correctly,and does not appear to have been hit anywhere that would cause the tranny to sit higher up toward the floor from what I can see.

Is the combination of the M22W and the Lakewood making the tail of the trans (hence yoke) sit in a different part of the floor tunnel, causing the intereference problem?

Could my driveshaft be too long? I know that when the car is on a lift with the rear wheels hanging, that the yoke is all the way into the tranny as far as it can go. When the car is sitting level, I'd say there is about 1/2" (maybe more) from the end of the tranny tail to the edge of the yoke. I really dont know of the origin of this driveshaft other than it was in the car when I bought it.

As usual, any help or wisdom is appreciated!!

Do your headers hit the frame/crossmember under the engine (honestly!). I installed new headers that hit that front crossmember under theengine, and this would NOT allow the engine/trans to drop down in the back. I could slide the trans crossmember in place without a jack under the trans... Once I "clearanced" the headers, the trans would hang down lower...

I did modify my tranny cross-member by cutting off the mount pad and fabricating a new pad about an inch lower (in my case, this was to lower the shifter). Be sure to check the driveline angle afterwards if you go this route, as well as shifter-to-crossmember clearance...


Another place to look at is the body-to-frame mounts... If these have deteriorated, the body could have dropped down relative to the frame (and the trans is attached to the frame...). Not sure on how much clearance there should be between the body and frame...

Tony:


I think the headers are clear, but I will re-check tonite. I dropped them in when the engine was being put in, and dont remember having any issues (dynomax).

I will start looking at the driveline angle tonight.

The body to frame mounts are a definite question. I had looked at the front ones when the engine was out, and they appeared to be in good shape. Not sure about the others. Also, if they are in good shape..I guess they could be the wrong ones..maybe some of the newer style poly bushings would be taller and allow the body to sit up higher and give me more clearance.(?).

Thanks for the ideas!

One other question..when I switched from the 350 to the 396, I left the frame mounts in the same spot, as I thought that this all was left alone.

Should I have changed the frame mount or location to allow the motor to sit lower in the frame?

JTM,

What year and engine? (doh! 69SS... Nevermind)

I too have the Dynomax headers, and therein lies my problem...

The first time I dropped the engine in with the new headers (WITHOUT the transmission), the engine sat so high in the back, that I could NOT get the transmission into the bellhousing (the trans was hitting the tunnel floor)...

I have a BB in a 66... Dynomax has since changed their catalog so that their headers no longer are correct application for 64-67 BB Chevelles, only 1968 and up...

Unreal! I have been fighting with fit issues of various parts (especially repop stuff)..It makes me nuts when things dont fit/work as advertised..but then again this site is a great way to avoid much of those hassles.

I like the dynomax fit in my car, but they are snug! I have an oil filter access issue, and have been forced to use the short filter, which I am not really happy about..it was either that or start denting things, and I figure I can change the oil every 1000 miles if I need to, as this car is not a daily driver.

Did you use a poly trans mount? It's quite a bit taller than stock, changing back to factory mount cured my u-joint hitting the floorboard problem.

Ok, checked the headers..they are definitely clear of the frame, and are not holding the motor up.

I have been using stock replacement type trans-mounts. I wanted to use the poly one, but I had seen that it was taller.

While on the topic of the transmission mount..I know the mount that I originally took out of the car looked different than the ones I have recently purchased. The old one (that I threw out, of course-duh) seemed thinner, and it had a metal tab that came out of it and engaged with the slot in my crossmember. Has anyone seen this type??

All of the replacement mounts I have purchased locally look the same (beveled edges).

Tonight I looked in my 1969 chassis service manual, page 6-41..and it shows TWO different types of rear engine/transmission mounts. Figure 31V on this page shows a different style of mount for a 396 or 427, and leads me to believe that the crossmember was slightly different for a BBC(?)..by different I mean that it shows a different mounting point for the SB mount vs. the BB mount, and the mounts look different. The service manual applies to chevelle/camaro/nova, and corvette..

The mount shown in this figure looks a lot like what I took out of the car and threw out! Anyone seen one like this or know where I should look for one?