driveshaft too short

[couttsdesign]

I'm in the process of a 5 speed transmission swap (Getrag 265) and the problem I am having is that my driveshaft is too short by about 1/2 inch. I think the shop where I had my d-shaft shortened may have done it incorrectly because now my driveshaft seems to be one continuous unit, in other words, the front section does not longitudinally slide in and out of the rear. Is the front section of the driveshaft supposed to be able to slide in and out of the rear section of the driveshaft? Is the driveshaft length supposed to be a constant length or is it designed to have slight longitudinal movement at the center bearing??

 

[sfdon]

Keep in mind that you have options with the flange length if your driveshaft is too short.

 

[Bill Riblett]

Driveshaft for 5 speed conversion

Keep in mind that you have options with the flange length if your driveshaft is too short.

Do you have part numbers for these?

I used a driveshaft for a 3.0CSA automatic transmission for my 5 speed conversion when I did it years ago.

Initially the driveshaft was a little short - 1/2"-3/4". I was able to make up the difference at the splined adjustment. This does not affect the center support bearing mounting, as the length of the rear section of the driveshaft is not affected.

 

[MMercury]

Do you have part numbers for these?

I used a driveshaft for a 3.0CSA automatic transmission for my 5 speed conversion when I did it years ago. Initially the driveshaft was a little short - 1/2"-3/4". I was able to make up the difference at the splined adjustment. This does not affect the center support bearing mounting, as the length of the rear section of the driveshaft is not affected.

Bill, do you know whether your donor drive shaft came from a car equipped with a BW trans or a ZF trans? Using the measurements available in the shop manual, it may make a difference. Complete length for BW equipped version appears to be 1454.7mm. Complete length for ZF equipped version appears to be 1452.5 mm (early style giubo?) or 1444mm/1444.5mm (reinforced flex disk?)

Determining which drive shafts interchange with 5-speed upgrades is not as simple as it may seem, or at least not to me. As part of his informative write-up, Carl N. advises: "shorten a 4 speed by 3.75 inches or lengthen an automatic .75 inches, replace u-joints as necessary, replace center carrier bearing and renew hardy disc." In the 1996-version I read, there is no mention of any possible deviations in preexisting drive shaft and/or giubo lengths.

The shop manual and its amendments presents various lengths for the front and rear drive shaft sections. This likely reflects differences in transmission lengths (ZF, Getrag, and BW and ZF). There may be other variables too, such as giubo style or flange length, per sfdon. I said "may," having not closely analyzed the numbers - and earlier transmission length measurements are long gone.

 

[sfdon]

The three flanges come from the early 265, late 265 and lastly the late 260 [finned version]
3/4, 1 1/4, 1 3/4 inches.

Keep in mind that there are 3 Guibos
30 mm
35mm
45mm

2 auto trannies depending on e9 or e3
bw 65
zfhp-20

2 manual trannies depending on e9 or e3
getrag 262
zf

Yes - the spacers exist on the flange- I found them on a getrag CR tranny out of a Alpina B7 this weekend.

 

[Bill Riblett]

Bill, do you know whether your donor drive shaft came from a car equipped with a BW trans or a ZF trans? Using the measurements available in the shop manual, it may make a difference. Complete length for BW equipped version appears to be 1454.7mm. Complete length for ZF equipped version appears to be 1452.5 mm (early style giubo?) or 1444mm/1444.5mm (reinforced flex disk?)

Determining which drive shafts interchange with 5-speed upgrades is not as simple as it may seem, or at least not to me. As part of his informative write-up, Carl N. advises: "shorten a 4 speed by 3.75 inches or lengthen an automatic .75 inches, replace u-joints as necessary, replace center carrier bearing and renew hardy disc." In the 1996-version I read, there is no mention of any possible deviations in preexisting drive shaft and/or giubo lengths.

The shop manual and its amendments presents various lengths for the front and rear drive shaft sections. This likely reflects differences in transmission lengths (ZF, Getrag, and BW and ZF). There may be other variables too, such as giubo style or flange length, per sfdon. I said "may," having not closely analyzed the numbers - and earlier transmission length measurements are long gone.

My driveshaft came from a 73 3.0CSA, which I think had a Borg Warner. I also had a driveshaft from a 70 2800CSA and my recollection is that it used smaller bolts than the 3.0 shaft. Unfortunately, I did all this over 20 years ago so I'm going by my now fuzzy memory.

I'm pretty sure that all the E9 driveshafts have the same length rear section, as the center support bearings for all mount in the same place. Remember that the shop manuals cover both E3s and E9s and there may be a difference between them.

No doubt it would be better if my driveshaft were lengthened 1/2-3/4", but it has survived many years, including some autocrosses, and I have a 230hp engine.

 

[sfdon]

Bill- you are right about the smaller bolts, however the flange is the same size so the bolt holes just need drilling.

 

[MMercury]

I'm pretty sure that all the E9 driveshafts have the same length rear section, as the center support bearings for all mount in the same place. Remember that the shop manuals cover both E3s and E9s and there may be a difference between them.

If you abide by the specifications contained in the shop manual amendments, drive shaft lengths varied, for coupes and sedans over the years. This apparently includes E9 rear sections too (from 2mm to 20mm). Notice the measurement lines also include the flanges.

Amendment (1-76) at bottom, has the rear section for the manual trans equipped E9 at 1035mm and auto equipped E9 at 1055mm. This is different than previous amendments which have all rear sections at, or near, 1055mm (1056.5mm 1057.2mm?) (Note that the CSL w/ 3.15L engine - rear section is 1044.8mm in 1975 and then shrinks to 1035mm by 1-76. Different differential output flanges?)

If the 1035mm is a typographical error, the typo is also in inches. (I suppose, if the body has only been subjected to indirect sunlight and has not shrunk over the years, the center bearing block may have enough latitude to accommodate 20mm.:wink: Maybe a later vehicle's center bearing block could be adapted to the E9 for this purpose.:?: )

FWIW: 72-75-76

 

[cpeavey]

Do you have part numbers for these?

Initially the driveshaft was a little short - 1/2"-3/4". I was able to make up the difference at the splined adjustment. This does not affect the center support bearing mounting, as the length of the rear section of the driveshaft is not affected.

Bill,

The splined joint is actually in the rear portion of the shaft, behind the center bearing, right? This is the problem with using the auto driveshaft and extending the joint to compensate - it does stress the bearing because you're making the rear section longer.

Charlie