Production Data 83 - Nostalgic British Cars

142
Front Suspension TR4A
ill. Part Number Description Qty. Details
No
Req.
Front Suspension TR4A
See also Performance & Tuning in Accessories for our full range of uprated suspension components.
The front suspension from the TR2 to the TR6 series of cars was of the same basic design throughout the whole
production period of the cars. It was in fact based on the Triumph Mayflower saloon of the early 1950’s.
For the technically minded it’s an unequal wishbone suspension with a coil spring & a telescopic shock absorber.
The actual design is in three main phases.
The TR2 through to the very early 1962 TR4’s (chassis number CT6343 wire wheels, & CT6390 steel wheels), had
the same basic design with the early type of upper ball joint (these are not handed), as it is called in Triumph
parlance. The vertical post joining the upper ball joint & lower trunnion has zero castor. The later TR4’s from the
above chassis numbers had a three degree castor system, which was also introduced with an improved top ball
joint and necessitated the trunnions to be handed to achieve the angling of the vertical posts, and also offset the
upper wishbones. The three degree angle means that the top of the vertical post is nearer the rear of the car than
the bottom end screwed into the trunnion.
The TR4A, whist using the same basic design, used completely redesigned components involving a new method
of bushing the trunnions to the lower wishbones, with a removable pin being used through the trunnion which
made ‘strip & re-assemble’ a much easier process. The lower inner wishbone bushes were also simplified to be
a simple rubber to metal bonded item. The inner upper wishbone bushes are made of rubber and remain the same
from the first TR2 to the last TR6. The TR4A suspension continued with little modification through to the last TR6.
1 200659 FULCRUM PIN, upper 2
2 GHF105 SCREW 8
3 GHF333 WASHER, locking 8
4 133504 ARM, wishbone upper front 2
5 133507 ARM, wishbone upper rear 2
6 102228* BUSH, rubber, upper wishbones 8 Standard
TT3062* BUSH, Polyurethane, upper wishbones 4 Uprated
NI QHQSK199S BUSH KIT(rubber bushes), upper/inner 1
TT3160 UPRATED BUSH KIT, upper/inner 1 see ‘Uprating Your Suspension’
7 WM69 WASHER, fulcrum pin 4
8 NL607041 NUT, fulcrum pin 4
9 PC10 SPLIT PIN, fulcrum nut 4
10 GAC6067X MAJOR SUSP’ OVERHAUL KIT 1 Standard bushes
GAC6067P MAJOR SUSP’ OVERHAUL KIT 1 Polyurethane bushes
Both kits repair both sides and include all items marked*
11 GSJ131 BALL JOINT (original) 2
GSJ131B BALL JOINT (non-original) 2
12 UKC3466 RUBBER BOOT, ball joint 2
13 138869 CLIP, ball joint boot 2
14 UHN445 GREASE NIPPLE 2
15 112347 BOLT, ball joint to wishbone 4
16 GHF223 NUT, nyloc, ball joint bolt 4
17 GHF302 WASHER 4
ill. Part Number Description Qty. Details
No
Req.
20 307216 VERTICAL LINK, LH 1
307215 VERTICAL LINK, RH 1
The TR4A vertical posts have a threaded hole for a grease nipple. The workshop manual recommends using a
EP90 weight gear oil. We have always preferred LM grease as lubricant for the front suspension.
The TR4A system involves pumping the grease down the centre of the vertical post, and then up through the
trunnion thread from the bottom. When you strip the suspension down, always be sure to thoroughly clear the
grease passage in the vertical post.
23 NL608041 LOCK-NUT, link to ball joint 2
24 WC112081 WASHER 2
25 307212 TIE ROD LEVER, LH 1
307211 TIE ROD LEVER, RH 1
30 133500 MOUNTING PLATE, LH 1 { brake caliper
133499 MOUNTING PLATE, RH 1 }
33 118324 BOLT 1 { mounting plate to
34 SH606065 SCREW 2 } vertical link
35 GHF223 NUT 2
36 106641 TAB WASHER 4
39 GHF126 BOLT 2 { mounting plate
40 BH606281 BOLT 2 } & tie rod lever
42 107106 DISTANCE PIECE, mounting plate 4
43 GHF223 NUT 4
50 115763 STUB AXLE 2
51 WC112081 WASHER, stub axle 2
52 GHF275 NUT, stub axle 2
GHK1021 BEARING KIT 2 includes items marked †
55 GHS110 † OIL SEAL 2
58 GHB111 † BEARING, inner 2
60 114284 HUB (Steel) (with studs) 2 {
114284A HUB (Alloy) (less studs) 2 |
114284X HUB (Alloy) (less studs) 2 |
(with extra thick flange for adjustment) | for steel wheels
61 114282 STUD, front (standard length) 8 |
114282X STUD, front (extra long) 8 |
(may need shortening to suit application) |
62 109586 NUT, wheel 16 }
65 114283 HUB, (includes studs) 2 {
66 114281 STUD, hub to extension 8 |
67 110366 NUT, extension to hub 8 | for wire wheels
70 217603 SPLINED EXTENSION, LH 1 |
217602 SPLINED EXTENSION, RH 1 }