Gearbox Swap

[stockman1]

What would be the benefits or detractions of installing a T5 from a 5.0 into an SVO. I know the gearing is a bit different but not sure exactly how?

[Laredo]

The 5.0 trans will have shallower gear ratios (lower RPMs) because the V8 torque curve is lower on the Rpm scale. Might save you a bit on fuel economy but your car will likely feel like a turd trying to accelerate.

[Laredo]

Google "T5 gear ratio chart" and you'll be able to calculate your RPM change.

[stockman1]

Google "T5 gear ratio chart" and you'll be able to calculate your RPM change.When I found and restored this 86 SVO, I changed the clutch and flywheel. At that point I believe someone before may have swapped the trans from a V8 car?? Input shaft dia. too large was the clue. I had the "SHAFT" machined to the proper dia. and all was fine. Now that I have the motor running properly, in premium setting the clutch slips under boost 4 to 5000 RPM and then catches again. I am not sure if the clutch I got was for a non turbo 2.3l or if the input shaft is too short? In low boost mode it is ok and speedo reads 10 mph too high.

Is anyone selling a T5 for the 86 SVO, or is there a company that has reman. T5's for the 86 SVO thanks?

[stockman1]

13-52-066-908 83-84 Ford NON-WC I cant find a tag on the trans but found this code on tail shaft LHS?

[FoxChassis]

Casting/part numbers on various parts of the trans are not very useful, or are difficult, in determining what it is.

Originally-installed T-5 trans will have a partial VIN stamped on the passenger side of the main case, where it bolts to the bellhousing. Give me that VIN and I can tell you if it's from a 2.3L, 2.3T, or 5.0L.

[stockman1]

Casting/part numbers on various parts of the trans are not very useful, or are difficult, in determining what it is.

Originally-installed T-5 trans will have a partial VIN stamped on the passenger side of the main case, where it bolts to the bellhousing. Give me that VIN and I can tell you if it's from a 2.3L, 2.3T, or 5.0L.FOX thanks, I know this trans is a non WC out of a 5.0. What I don't know is if the shorter input shaft and/or the clutch is causing the slipping?

[MikeFleming]

Clutch is the ony thing (other than tyres) can can cause "slipping". By the time the gears get worn enough to "slip", there are very loud noises with a sudden loud bang and immediate loss of drive.

And stop loading it to where it slips. Slipping under load will quickly overheat (and damage) the flywheel and pressure plate.

The pre-WC gearboxes have the same input shaft length as the WC ones up until 1993-something for the sn095 cars, whihc is longer iirc.

The biggest issue with the non-4-cyl gearboxes, imho, is the rather large gear spacing between 4th and 5th gears. It will get you to 2000-2200 at freeway speeds, which is way out of the torque band and heavy in the worst engine NVH for the 2.3L T.

The typical v-ate 5-speed has a 3.35 first gear which is not that much different from the SVO 3.51 first. And the other three are slightly closer together than the 4-cyl gearset.

The Red Baron has the 3.35 gearset with a 0.82 fifth (versus the more common 0.67). So the spacing between all gears is almost identical.

[FoxChassis]

NWC V8 T-5 has 2.95 1st

[stockman1]

NWC V8 T-5 has 2.95 1stwhich is it 2.95 or as MikeFleming says 3.35?

[k98dave]

When I found and restored this 86 SVO, I changed the clutch and flywheel. At that point I believe someone before may have swapped the trans from a V8 car?? Input shaft dia. too large was the clue. I had the "SHAFT" machined to the proper dia. and all was fine.

I know there is a pilot bearing made that will allow a 4 cyl trans to work with a v8 but is there the reverse for a V8 trans behind a 4Cyl? My son has his 93 4cyl coupe for a work DD car and the stock trans is very noisy, believe the input shaft bearings are on the way out. I have been looking for rebuilt 4 cyl trans but all I can find are the V8's

[svono50]

I guess it could be debated, but most of the published literature and info out there points to the NWC having a 2.95 1st gear set. I do know that the 84 SVO's with the NWC had a 4.03 1st gear ratio...at least the one I purchased back in the day and swapped into my former 80 Mustang 2.3L and that my 86 WC has a 3.50 1st gear. Here is a popular block of information on the T-5's and one of the most common you will find out there:

http://www.allfordmustangs.com/Detailed/349.shtml

[MikeFleming]

The WC box commonly came in two gearsets for Fords: 3.35 and he 2.95. Iirc the 2.95 was only available from the Ford Motorsports/SVO catalog. It was rated to a higher ft-lbs value. 300 (3.35) vs 330 (2.95) in the WC, iirc.

[stockman1]

The WC box commonly came in two gearsets for Fords: 3.35 and he 2.95. Iirc the 2.95 was only available from the Ford Motorsports/SVO catalog. It was rated to a higher ft-lbs value. 300 (3.35) vs 330 (2.95) in the WC, iirc.really confused this box Is nwc and looks like its from 83 or 85 due to a casting stamp? The shaft was for a v8

[MikeFleming]

WC boxes didn't exist until 1985.

BTW - I'm gonna change the thread title. Outside of Florida "tranny" means something else entirely and, in proper British terminology, autocars come with gearboxes. A "transmission" is something made and received on the wireless.

Just sayin'!

[svono50]

With all the parts that can interchange in the T-5 world, unless you know exactly where the 'gearbox' came from, it is all speculation as to what you really have. You could map out your rpm/speed in each gear to try and figure it out or pull it and see what gear sets are really in there and its true source.

[MikeFleming]

Disassemble and count teeth. And write it down. Then we will know.

Iirc Motion Dynamics used to sell a brass/bronze pilot bushing to adapt between the larger v-ate snout into the smaller 2.3 crank (have one in the Red Baron that required "fitting"). I don't recall seeing a needle-type bearing that will fit that application.

[stockman1]

Does anyone have experience with either Midwest Transmission or Man-trans as a rebuild service? I am negotiating with them for a Borg Warner 1352-116 build. They are trying to find the correct gear sets. I should know more tomorrow. Man-trans was able to find the -155 gear set from the 87 turbo coupe, gearing is close to what the orig. SVO had but the torque rating is 10 ft-lbs lower. Any suggestions?

[svono50]

The 155 gearset is almost identical to the 114 gearset that came in the 84-85 SVO's, which was paired with 3:45 gears out back. The 3.97 1st combined with 3.73's will give a pretty short 1st gear (14.81 vs 13.06:1), but not too far off from what I am currently running with 4.10 gears (14.35:1). Your 5th gear will basically be stock with the 155 as well. I wouldn't worry about the torque rating unless you plan on drag racing a lot and throw a set of slicks into the mix.

If they can't find a set of the 116's, then any of the 3.97-0.79 sets should work (155, 162, 194, 207 or 209). Your shop would have to confirm if any of the other sets will work with your boxes internals. Good luck.

[stockman1]

Well here is an update: Got a new SPEC clutch and my mech tells me that the rear main seal was in crooked and was leaking oil all over the new-older clutch, thus causing the slippage.

The last clutch was a Valeo and was correct OEM, it was the seal that was in wrong.

New SPEC clutch installed along with new main seal. This is the interesting part, TAG off gearbox says 1352-034 which is non WC 1983 SVO 5.0 V8.

Questions? 1. Gearbox has ATF in it and should have 90w, is that bad? 2. When putting in the injectors I think I may have inadvertently caused the dipstick to leak, is there an O ring that seals it? thanks.......

[MikeFleming]

Questions? 1. Gearbox has ATF in it and should have 90w, is that bad? T5's have NEVER come with gear oil. Any of them. ATF (or similar weight synthetic oils) are correct. Things insideh te box would not work well with a thick oil like 90w.


2. When putting in the injectors I think I may have inadvertently caused the dipstick to leak, is there an O ring that seals it? thanks....... Factory only uses an interference fit between the dipstick tube and block. Over time they become less press-fit and "leak free". Ive had *some* success by installing an o-ring onto the bottom of the tube - keep in mind it will raise the tube by the thickness of the ring - and use the attaching support bracket on the top end to "compress" the ring for some sealing effect. Ultimately not a totally leak-proof design.

More better [and a whole lot more trouble] is to use a sealing compound on totally clean, oil-free surfaces and bolt/load it in place until the sealant cures. en never move that tube again. Downside is that most compounds that will seal that area dry it a hard material, which will break off and get in the oil anytime you remove or twist the tube. So it's trade-off.

Start with a small diameter neoprene or viton o-ring.

[stockman1]

Thanks Mike, I thought I read or was told that NWC t5 used Gear oil......

[MikeFleming]

Thanks Mike, I thought I read or was told that NWC t5 used Gear oil...... While you may have very well read it *somewhere*, BW boxes have been using ATF since the mid-70's. I recall the first time I drained the fluid out of a Cosworth Vega gearbox to replace a broken shift fork and the fluid was very thin and bright pink.

[svono50]

There is a lot of misinformation out there on what fluid to use in the NWC boxes, from using straight 50W, 70W, 75-95W, etc. I transplanted a NWC T-5 from an 84 SVO in my former 80 2.3L NA Mustang and can speak from the mistake of dumping in gear oil. It worked fine till temps dipped below 55 deg, when it then felt like the shifter was moving through tar. Once warmed up it was OK again, but I had to double clutch it till the gear oil warmed up. Put in Mobil 1 synthetic ATF and haven't looked back in that car and my current 86 SVO.

As for the dipstick tube, I have seen some folks use a light coating of either Ultra Black or Ultra Blue RTV on the OD of the tube and slide it back into the block. Make sure both surfaces are nice and clean though otherwise you will likely not get a good seal. YMMV.

[FoxChassis]

Original fluid in all Ford T-5s, whether they be standard duty ("Non-World Class") or heavy duty ("World Class") was Dexron II-D automatic transmission fluid. Dex II-D has not been made for quite some time. Dex III was an acceptable replacement for Dex II-D but that too is no longer made. Tremec, which bought Borg Warner's transmission division in 1998, says 30W (not 10W-30) oil is an acceptable replacement for Dex II.