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Anyone install a 5-speed tranny? which one?

reamer

Contributor
Bronco Guru
Joined
Mar 20, 2008
Messages
1,249
Just put a ZF 5-sp in my 1986 F-150, replacing the no-OD NP435.
runs much lower on the tach. on the highway..
What has been successful installing into a E.B.?
 

NYLES

Bronco Guru
Joined
Aug 13, 2004
Messages
9,846
ZF Needs a lot of gears, I run 5.13 and 37 inch tires, 5th not needed unless running hwy speeds.
 

thegreatjustino

Contributor
Red Head Grease Monkey
Joined
Jan 23, 2002
Messages
15,624
Loc.
Stockton, CA
ZF, NV-3550, NV-4500, Mazda M5OD are all common swaps. As was said simply swapping the transmission isn't going to do much unless you've got the the proper axle gearing to use both first gear and the over drive.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,835
Also the AX-15

In the past there was also a kit for the T-5 which has been discontinued. And something to avoid if found. That has a really crazy OD and the innards are made of glass.

I think there is another 5-speed but I can't think of what it is.
 
OP
OP
reamer

reamer

Contributor
Bronco Guru
Joined
Mar 20, 2008
Messages
1,249
Yes I'm thinking of t a street Bronco, with highway in mind,
 

bsquared

Contributor
Sr. Member
Joined
Dec 4, 2010
Messages
960
I did the ZF + NP205 conversion about 6 years ago and love it. Running 4.11 gears on 31's and haven't found an overpass yet it couldn't climb in OD. It's a great upgrade.
 

bronconut73

Bronco Guru
Joined
Aug 7, 2012
Messages
9,916
AX-15 and M5OD seem to be the hot ticket right now for a mild trail street cruiser.

The ZF-5 and NV4550 are the "go to" tranny for harder core wheelers.
 

RADO

Jr. Member
Joined
Sep 26, 2016
Messages
138
Loc.
Phoenix
I installed an AX-15 this year and have been really happy with it. I found a rebuilt unit pretty cheap locally and spent about $1200 on the bell housing & Dana 20 adapters. I also added a B&M short throw shifter. Drives great around town and on the highway. I could use a bit more gearing off road, but I'll solve that with an atlas II someday.
 

Nothing Special

Sr. Member
Joined
Nov 25, 2016
Messages
804
I have an NV3550 in mine (with 4.10 gears and 33" tires). It's great for the kind of driving I do as an old man living in the suburbs. And off-road it has a nice gear spread and easy shifting to work with my Atlas 4.3:1.

I picked it because I absolutely hated the two ZF6 trannies that were in my '08 F-250 (Ford eventually bought it back from me on a lemon law claim), so I wasn't eager to try another heavy-duty ZF. I thought about an NV4500, but the price was higher and I didn't feel I needed the strength between a mild 302 and an Atlas. A friend had an NV3500 in an S-10 and that seemed like a nice trans, so I went with the 3550.
 

77RHINO

Full Member
Joined
Feb 22, 2011
Messages
308
NV3550 here as well, and 4.56s. Currently running 33s, but will be moving to 35s next which should work even better with the OD. It's been a great trans so far, no complaints.
 

ntsqd

heratic car camper
Joined
Jan 30, 2005
Messages
3,229
Loc.
Upper SoKA
The 3550 looks a lot like a Tremmec 'T-5' to me. Not ALL T-5's have a horrendous OD ratio, just most of them intended for Ford applications.
http://www.britishv8.org/Articles/Borg-Warner-T5-ID-Tags.htm I have one in a street car and I like it a lot.

Sorry, when ever anyone says "trannies" lately I flash on this:
i-rRdxxTH-Th.jpg
 

661buster1963

Full Member
Joined
Feb 18, 2009
Messages
287
I have seen conflicting reviews on whether the AX15 or the Nv3550 is the 'stronger' transmission. They seem very comparable in design, gear ratio, factory applications. is it that they are to comparable to differentiate or is one or the other a little stronger, looking for opinion. I have a 375 ft-400 ft# 351W planned for my 68, which wont see much offroad use.
 

RADO

Jr. Member
Joined
Sep 26, 2016
Messages
138
Loc.
Phoenix
I have seen conflicting reviews on whether the AX15 or the Nv3550 is the 'stronger' transmission. They seem very comparable in design, gear ratio, factory applications. is it that they are to comparable to differentiate or is one or the other a little stronger, looking for opinion. I have a 375 ft-400 ft# 351W planned for my 68, which wont see much offroad use.

Hard to say...

The AX-15 doesn't seem to have the GVWR rating spec'd like the NV3550, but the general consensus is they're similar in strength due to the application. Many will lean toward the NV3550 because the ratings are actually posted, 300 ft/lbs torque @ 7,200 lbs GVW

The only issue with the NV3550 is that the transmission is no longer in production, where as the AX-15 can still be purchased new. I found a much better deal on an AX-15 locally because the transmission was more readily available. This is the only reason why I chose the AX-15 over the NV3550. I only have a few thousand miles on the AX-15, but no issues to report (351W, 4.88 gears, 35" tires).

For a built or stroked 351W, I would go with a truck transmission, Ford ZF or NV4500. Both the NV3550 & AX15 are designed for 6 cyl. engines and will have limitations. I think we get away with using these transmissions successfully in the Bronco because of the lower GVWR.
 

bearskinner

Full Member
Joined
Feb 22, 2011
Messages
292
Loc.
N.Idaho, AK, SoCal
NV3550 here as well, and 4.56s. Currently running 33s, but will be moving to 35s next which should work even better with the OD. It's been a great trans so far, no complaints.

I am running a NV3550 with 4:56 gears and 35" tires, and feel you could easily go with a deeper gear. 4:88 or 5:13 would be fine. I cruise at 75 all over at 2550 RPM, but need to go to 4th on any hills. I wanted to move to 37's but I believe it would turn it into a 4 speed.
 

t120r

Sr. Member
Joined
Nov 25, 2008
Messages
629
I installed a ZF/NP205. Not a bolt in swap as the mount gets mover 3"aft, which means the front driveshaft gets extended and the rear gets shortened.Also the NP205 needs a custom mount made.
 
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