CMP chassis

[T. Metsovitis]

I've been searching the web for pictures and/or drawings of the chassis on which the 15cwt, 3 ton and 6x6 CMPs were based on but I didn't manage to find much. Can anybody please point me in the right direction?
Thanks in advance
Fyll

[cliff]

there is not much in the way of drawings out there. I assume you want them for scale modeling? I do have some photos of a Ford Chassis taken by Tony Smith as well as some underneath shots of a C60X. From there I am afraid you have to scale it as best you can.

I will past the pics if you want them a little later when I have more time. OR PM me your e-mail address and I will send what I have directly too you.

Cheers
Cliff

[Tony Smith]

From the Australian Army Driver's handbook, the following lubrication diagrams should assist:

Ford F60L 158" wb:

[Tony Smith]

Ford F60S 134"wb:

[Tony Smith]

Ford F15A 101"wb:

[Tony Smith]

Ford F-GT 101"wb (use this to fix the Tamiya mistakes!):

[Tony Smith]

While the Chev versions are generally of the same arrangement, naturally the Engine/Gearbox mounting is different.

Chev C15A:

[T. Metsovitis]

Hi Tony,

These diagrams are excelent! I was hoping somebody would come up with something like this. Many thanks!

Fyll

[Keith Webb]

Originally posted by Tony Smith
Ford F-GT 101"wb (use this to fix the Tamiya mistakes!):

The FGT drawing should show the larger fuel tanks and the battery box inside the cab behind the gear levers rather than in the usual place on the step. On Australian Fords and some Chevs, the fuel fillers are to the rear of the tanks to clear the crew doors. CGT 8 appeared to just have a cutout in the lower part of the door to clear the filler.

[gjamo]

This may be of help

[David_Hayward (RIP)]

Are there any drawings of the 4 x 2 chassis please? My lube chart does not show the chassis frame rails. I assume that there are somewhere the F60H/C60X drawings, but in the meantime may I also thank you for the postings!

[sapper740]

Originally posted by Keith Webb in Have "Bofors" will travel
They would probably look like these, Rolf?



This pic comes from Brian Gough's book of Chevrolet factory images.

Kieth, What weight and model truck is in this picture? I've been trying to I.D. the CMP I bought recently, as well as what it may be missing and this pic is exactly the same as mine. I was wondering what was missing from the bracket between the frame rails. It looks like a p.t.o. winch. What was this used for? My truck has the same size, offset rear differential also. Any info would be greatly appreciated! Any ideas on where to find such a winch?

[Tony Smith]

David, it's an educated guess on my part, but I've taken the liberty of posting the C15 . Interestingly, note the C15 has auxillary springs while the C15A does not!
The Ford and Chev Australian Army Driver's handbooks are published in 1945, but there is no mention in either of the F60H or C60X.

[sapper740]

Originally posted by Tony Smith
While the Chev versions are generally of the same arrangement, naturally the Engine/Gearbox mounting is different.

Chev C15A:

Hi Tony. Whilst trying to identify the particular model of CMP I recently purchased, I came upon an old post from Rob Fast, dated Aug 19, 2003. The post was titled," Cab 11 rear fairleads" and was following the thread, "Have Bofors will travel" The picture Rob posted is near identical to my truck....same differential and frame members, 'though mine is missing the winch. I'm beginning to think my CMP is a C30 LAAT, if that is indeed what Rob's post is showing. Do you have any pics or diagrams of such a vehicle? I looked at the pics you posted and none of them matched my vehicle. Any help would be greatly appreciated! Thanks, Derek. Chimo!

[David_Hayward (RIP)]

1. Thanks very much Tony for your effort. Query: why did the 4 x 2 have auxiliary springs and the 4 x 4 not unless this was a later mod?

2. I have it seems census data on two batches of British LAAT C30s, and photos of representatives of both. If these have not been posted previously let me know and I shall do the honours.

[Tony Smith]

Originally posted by David_Hayward
1. Thanks very much Tony for your effort. Query: why did the 4 x 2 have auxiliary springs and the 4 x 4 not unless this was a later mod?

I can only speculate that the location of the front springs on the C15 being further inboard would have would have given rise to pronounced body roll on a Cab-Over design and required the Auxillary springs on the back to try and stiffen up the roll but not the ride?

[Tony Smith]

Originally posted by sapper740
Do you have any pics or diagrams of such a vehicle? Thanks, Derek. Chimo!

[David_Hayward (RIP)]

Thanks once again! I continue to believe that the 15-cwt 4 x 4 designs were later than the 4 x 2 in the development progtramme. The very first CKD exports to England were of 8-cwt and 15-cwt 4 x 2 chassis.

This has of course been discussed before:
THREAD RE SPRINGS

[Tony Smith]

Originally posted by David_Hayward
This has of course been discussed before:
THREAD RE SPRINGS

As discussed in that thread, while the C15 has Auxillary springs, the F15 DOES NOT (PS I like the mis-matched front tyres in this drawing):

[David_Hayward (RIP)]

Amazing that the Chevrolet had auxiliary or helper springs and the Ford did not!

Auxiliary springs where used provide reserve capacity for heavier loads...
...Spring shackle studs are provided with lubrication fittings (except front springs of F-8 and F-15 models)....
...Spring shackle studs used on the front springs of F-8 and F-15 models are of the oilless type and require no lubrication.

: FORD SPECIAL PATTERN VEHICLES INSTRUCTION BOOK

[Hanno Spoelstra]

Originally posted by sapper740
I came upon an old post from Rob Fast, dated Aug 19, 2003. The post was titled," Cab 11 rear fairleads" and was following the thread, "Have Bofors will travel"

Have split and merged your posting from the "Have Bofors will travel" thread to this one for your convenience, Derek.

HTH,
Hanno

[David_Hayward (RIP)]

Thankis to Hanno for doing what I thought should have been done!

1. May I refer to the thread FATs a 60-cwt?

2. The chassis drawings for the F-30/F60S look very similar apart from the differences as mentioned in the thread. My question is: does this prove or not that the 30-cwt/60-cwt CMP chassis was a lengthened FAT chassis minus those components not required?

I also compared the FAT and F15A books, while the chassis assemblies differ for these vehicles ( FAT: C011QF-5005SA, F15A: C011WQF-5005SA), the left and right side rails on these vehicles ARE THE SAME! (C011Q-5015/6D, later becoming C011Q-5224/5D). The difference between the two assemblies relate to the transfer case crossmember, auxillary spring pads and the provision of winch mounts. Otherwise the FAT is a 15cwt!
...the other difference to the FGT chassis is the double rear crossmember with larger fishplates reinforcing it to strengthen the area where the fairleads mount.

3. I have been comparing the C15 chassis with the FAT and other 4 x 4 chassis and to these untrained eyes the chassis rails look similar but otherwise there is nothing that suggests that one begat the other. My research suggests the F15 chassis was independently designed from the 4 x 4 series [and I stress the Ford chassis not Chevrolet]. I believe and willing to be proven totally wrong that the FAT chassis was able to be the basis for the F30S/F60S and then the F60L. The F15A though was an adjunct of the FAT with common chassis components but with different transfer case, etc. from the other 4 x 4 chassis but has no apparent correlation with the F15 chassis.

4. Are there any drawings of the C8/F8 and C8A please as it would be interesting to compare them as well?

[Tony Smith]

Originally posted by David_Hayward
3. I have been comparing the C15 chassis with the FAT and other 4 x 4 chassis and to these untrained eyes the chassis rails look similar but otherwise there is nothing that suggests that one begat the other. My research suggests the F15 chassis was independently designed from the 4 x 4 series [and I stress the Ford chassis not Chevrolet]. I believe and willing to be proven totally wrong that the FAT chassis was able to be the basis for the F30S/F60S and then the F60L. The F15A though was an adjunct of the FAT with common chassis components but with different transfer case, etc. from the other 4 x 4 chassis but has no apparent correlation with the F15 chassis.

I can't stitch the pics together for a better comparison as the file becomes too big to attach. If you compare the F15 and F15A chassis side by side, the only differences are in the crossmember for the transfer case and the way that the rear of the gearbox is supported. In other respects, the chassis appear the same.
Comparing the C15 with the C15A, or indeed any of the other Chevs it is quite different, particularly around the front springs and would seem to be an orphan (or unmarried uncle in this family tree).
The C8/C8A chassis has more in common with 3/4 ton Commercial Chev chassis (including drivetrain) and would seem to be more of a hybrid of commercial vehicle with CMP cab, rather "pure" CMP. Unfortunately, the C8A/C8AX was not in use by the Australian Army, so it's chassis never made it into the handbook. (Still doesn't explain the absence of the C60X!)

[David_Hayward (RIP)]

Tony, I am obliged!

1.

Comparing the C15 with the C15A, or indeed any of the other Chevs it is quite different, particularly around the front springs and would seem to be an orphan (or unmarried uncle in this family tree).

I have begun to consider whether the C15 was developed by GM of Canada independently of the F15 whereas the C15A was an adapted derivative of the F15A, itself unique with its transfer case design. There is logic in this suggestion from all the evidence that I have gathered.

2.

The C8/C8A chassis has more in common with 3/4 ton Commercial Chev chassis (including drivetrain) and would seem to be more of a hybrid of commercial vehicle with CMP cab, rather "pure" CMP.

Tony, I am sure you are right on this one and that the C8/F8, C8A and presumably the F8A that preceded the C8A were based on the 3/4 ton commercial chassis frames as the 8-cwt pre-war British pick-ups that the War Department were trialling were all 15-cwt civilian-rated commercial chassis, 4 x 2 and 4 x 4 drive. So far as I can see the limited-production F8A preceded the C8A but drawings of its chassis may indeed be rarer than Rocking Horse manure!

[T. Metsovitis]

Thank you all very much for the continuing supply of so much interesting info in response to my original request.

Fyll

[David_Hayward (RIP)]

Thank you for starting a thread which has answered so many questions!

[David_Hayward (RIP)]

I have been trying to work out where the F-8, C011DF, chassis design came from. I think it is taken as read that the 8-cwt chassis were based on 3/4-ton or 15-cwt commercial chassis but there was no 1940 commercial Forward-Control or COE 101" wheelbase below 1 1/2 tons, though arguably that design formed the basis of the F-15. Apart from cabs, wheels, tyres, etc. was the F-8 downsized in the chassis department from the 15-cwt and above series? Lighter chassis rails perhaps or were they much the same?

I have just found evidence that suggests that the use of a Ford 30-cwt chassis to create a WD 8-cwt 4 x 4 has precedent. In theory therefore the F-8 and its successor the F-8A could well have originally been conceived as using 1 1/2 -ton components after all! Seems like overkill to me but I leave the comments thereon to you experts.

[Hanno Spoelstra]

Originally posted by Tony Smith
As discussed in that thread, while the C15 has Auxillary springs, the F15 DOES NOT

I know we went over this before, but could it be the early F15 chassis did have helper springs as opposed to later chassis? Pic below, from Colin Stevens' website, clearly shows helper springs on F15 Cab 11.

H.

[George McKenzie]

I have a # 11 F15A with helper springs and my #13 F15A does not ,both Fords . .I thought it might have been done this way depending what they were doing George

[cletrac (RIP)]

Here's a comparison of a C8 frame (on the right) and a civilian 1/2 ton frame. The frames are basically the same from the front to the crossmember at the u-joint and from there back the C8 goes straight back while the half ton keeps getting wider. This is because the half ton has the springs under the frame rails and the C8 has them outside the rails. The spring mounts on the rear ends are the same distance apart, but the half ton rear end is wider between the brake backing plates. The C8 uses the heavier 2 ton steering components. The positioning of the motor and crossmembers in relation to the front axle is the same on both frames.