700R4 crossmember

[chev-obsession]

Do the 700R4 tranny's require a 700R4 specific crossmember? Or can you use a turbo 350 or 400 crossmember?

[Mike Bradbury]

No you need one for the 700. It is a different length tranny, I have heard of some guys just unriveting the 350/400 cross member and aligning it with the 700 but I have never seen it in action. Now days they are ready made for many vehicles and are not too expensive.

[clinebarger]

You do not need to buy a cross-member.


Slide the cross-member back & drill new holes in the frame, You can use the 3 speed mount, just make sure to use metric bolts in the transmission case, they are 10 X 1.50mm

[Captainfab]

Exactly....there's no need for any kind of special crossmember. You just need an auto trans crossmember for a '66-'87 truck. You will need the correct trans mount for the crossmember, ie: single stud, or two threaded holes. Of course you can always drill a couple holes for the mount if needed.

Originally Posted by clinebarger

You do not need to buy a cross-member.


Slide the cross-member back & drill new holes in the frame, You can use the 3 speed mount, just make sure to use metric bolts in the transmission case, they are 10 X 1.50mm

[LEEVON]

yes...but, but, but...

Keep in mind that re-drilling the upper holes for the stock crossmember is next to impossible. Also, you will not have access to your rear transmission pan bolts which is a deal breaker for me on any trans swap. I hate moving a crossmember just to drop a pan, and with the 700R4 you will need to drop the pan and check on your TV plunger stroke if you're doing it right.

These two reasons were enough for me to cough up the $50 for a CPP crossmember which bolts on the bottom of the frame rails and has much more clearance.

[gchemist]

Make you own if you don't move your current one. I had a one made with dual humps for exhaust.

[chev-obsession]

does any one have dimensions/specs for the cpp or other aftermarket cross member?

[clinebarger]

Originally Posted by LEEVON

Keep in mind that re-drilling the upper holes for the stock crossmember is next to impossible.

I use a foot long 13/32" drill bit to drill the top holes from the bottem http://alliedboltinc.com/product/13/...BIT~51766.aspx

[SSedan64]

Originally Posted by clinebarger

I use a foot long 13/32" drill bit to drill the top holes from the bottem http://alliedboltinc.com/product/13/...BIT~51766.aspx

X2...A lot cheaper than a new Crossmember.

[chev-obsession]

Ok.... now let me ask this.....

Im running the baer rear disc brakes, its a short bed and running the 700R4, would I need to remove the e-brake crossmember? If so what would I need to do in order to add an e-brake? Or what is the solution to this problem becasue i know that some one has done this before.

[Captainfab]

Do your rear disc brakes have an e-brake? If so, you will need to fabricate something on the bottom of your trans crossmember for the cables, or else use the e-brake cable system from a '66-'72 truck. Member TR65 fabricated a trans crossmember for his truck to accomodate the e-brake cables. If you do a search, you should find it.

[chev-obsession]

ok ill look for it and yes the rear calipers have ebrakes

[ChevyJr]

Originally Posted by Captainfab

Do your rear disc brakes have an e-brake? If so, you will need to fabricate something on the bottom of your trans crossmember for the cables, or else use the e-brake cable system from a '66-'72 truck. Member TR65 fabricated a trans crossmember for his truck to accomodate the e-brake cables. If you do a search, you should find it.

I hope this isn't a stupid question, but can you simply flip the ebrake crossmember upside down? It should still serve the same purpose right? I am also doing a 700r4 conversion and would like to keep the original ebrake crossmember if possible. Even if that means sliding it further backwards and finding new cables at new lengths.

[chev-obsession]

Originally Posted by ChevyJr

I hope this isn't a stupid question, but can you simply flip the ebrake crossmember upside down? It should still serve the same purpose right? I am also doing a 700r4 conversion and would like to keep the original ebrake crossmember if possible. Even if that means sliding it further backwards and finding new cables at new lengths.

hey man, I tired flipping the original e-brake bracket at first. its located about the right length but the trans hung down way to low (bad angle) so I just went down to the wrecking yard and bought a trans x-member from like a 71 1/2 ton bolted it in and trans sits near perfect. as for the e-brake stuff I haven't got that far yet lol

[dwntwn]

You can use a stock crossmember if the transmission mount attaches at the tailshaft like in Persh's picture.

http://www.persh.org/images/65Pickup/Trans_Xmbr4.jpg

What I ran into with my 700R conversion was the transmission mount was further forward on the transmission.

This location interfered with the pan, so I trimmed the front of the crossmember—mainly because my truck had the parking brake assembly attached to the rear of the crossmember and I didn't want to lose that provision.

If your transmission mounts at the rear, it is true you can use a stock crossmember, and depending on your parking brake setup will have to either attach it to the crossmember or use the later style like Captain Fab suggested.

If you want the crossmember with the parking brake attachment already done, Bowtie Overdrives has one for $175.

I decided I didn't like the modified crossmember in mine so I went with the $79 CPP one. And while I'm doing it, using the later style parking brake setup.

Parking brake assembly:
I have a '70 c20 longbed parts truck in my yard. I don't know if the parts I removed are available aftermarket or you would need to go to a junkyard, but I can say with my install, all I need to buy is the intermediate cable. LMC carries it for $9.95, and it is the same part number '64-72, so even though the parking brake is different (hand brake vs pedal) the intermediate cable is the same.

I agree the mechanism is simpler, but I don't know if I would have gone to the trouble of converting to the later style if I didn't have the parts truck sitting 50 feet from my garage.

[lesauto]

Thanks for the info dwntown I'm ordering 1 from bowtie overdrive they look really nice. And since I have torsion bars on my 62 I don't have a lot of oppotions I could make one but it would not look near as good..

[KMAT]

Please somebody correct me if I'm wrong but aren't the crossmember for a turbo 350 and a turbo 400 different? And I'm not sure what of the two Transmissions were in this truck prior to buying it but my crossmember does not seem to want to bolt up properly to the transmission. Is it possible that I have the wrong rubber mount peace?

[Mr_Rich]

Originally Posted by KMAT

Please somebody correct me if I'm wrong but aren't the crossmember for a turbo 350 and a turbo 400 different? And I'm not sure what of the two Transmissions were in this truck prior to buying it but my crossmember does not seem to want to bolt up properly to the transmission. Is it possible that I have the wrong rubber mount peace?

Back when I still had my '69 Firebird project I was planning a 700R4 swap and my research turned up the fact that T400 trans and 700R4 trans have very similar mounting dimensions; within a fraction. The T400 crossmember is built so that it used the same T350 mounting holes on the frame. I still have that support/ crossmember for sale since my plans have changed. I don't know if it will work on trucks though. It's 31 1/2" wide and 30 1/2" between mounting holes.

[Captainfab]

No the crossmember is the same, just a different set of holes in the frame to bolt it in. A pic might help troubleshoot your issue.

Originally Posted by KMAT

Please somebody correct me if I'm wrong but aren't the crossmember for a turbo 350 and a turbo 400 different? And I'm not sure what of the two Transmissions were in this truck prior to buying it but my crossmember does not seem to want to bolt up properly to the transmission. Is it possible that I have the wrong rubber mount peace?

[KMAT]

Okay then i must have something else going on here then, mabey crossmembers been altered.I better pull it back out and have a better look see at it. THANKS for your response, will have a update on issue couple days.